27
Analyzing Brightness Variation of an SX Phoenicis Star (XX Cyg) Department of Physics & Astronomy Minnesota State University Moorhead(MSUM) Shouvik Bhattacharya 04.05.2013 4/5/2013 1
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1
Analyzing Brightness Variation of an SX Phoenicis Star (XX Cyg)
Department of Physics amp AstronomyMinnesota State University Moorhead(MSUM)
Shouvik Bhattacharya
04052013
452013
2
Outline
bull Background bull Senior Thesisbull Theorybull Methodsbull Results bull Conclusions
452013
3
Background
bull A star can be defined as a self-gravitating celestial object in which there is or there was (in the case of dead stars) sustained thermonuclear fusion of hydrogen in their core (LeBlanc 2010)
bull Variable stars vary their brightnessbull SX Phoenicis is categorized as a High
Amplitude Delta Scuti star
452013
4
Motivation
bull Took Introduction to Research in fall 2010 and read about pulsation theory
bull Observed SZ Lyn a Delta Scuti star back in spring 2011
bull Found out that there exists a research group named (Delta Scuti Network) in summer of 2011
bull Scientific Observations of XX Cyg began in fall 2011
bull Found that XX Cygrsquos period has been reported in 8 decimal places in spring 2012
452013
5
Senior Thesis
bull Brightness variation of XX Cyg in different optical filters
bull The period of XX Cyg (using the information on brightness variation in V and R filters) and compare it with the accepted value
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
2
Outline
bull Background bull Senior Thesisbull Theorybull Methodsbull Results bull Conclusions
452013
3
Background
bull A star can be defined as a self-gravitating celestial object in which there is or there was (in the case of dead stars) sustained thermonuclear fusion of hydrogen in their core (LeBlanc 2010)
bull Variable stars vary their brightnessbull SX Phoenicis is categorized as a High
Amplitude Delta Scuti star
452013
4
Motivation
bull Took Introduction to Research in fall 2010 and read about pulsation theory
bull Observed SZ Lyn a Delta Scuti star back in spring 2011
bull Found out that there exists a research group named (Delta Scuti Network) in summer of 2011
bull Scientific Observations of XX Cyg began in fall 2011
bull Found that XX Cygrsquos period has been reported in 8 decimal places in spring 2012
452013
5
Senior Thesis
bull Brightness variation of XX Cyg in different optical filters
bull The period of XX Cyg (using the information on brightness variation in V and R filters) and compare it with the accepted value
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
3
Background
bull A star can be defined as a self-gravitating celestial object in which there is or there was (in the case of dead stars) sustained thermonuclear fusion of hydrogen in their core (LeBlanc 2010)
bull Variable stars vary their brightnessbull SX Phoenicis is categorized as a High
Amplitude Delta Scuti star
452013
4
Motivation
bull Took Introduction to Research in fall 2010 and read about pulsation theory
bull Observed SZ Lyn a Delta Scuti star back in spring 2011
bull Found out that there exists a research group named (Delta Scuti Network) in summer of 2011
bull Scientific Observations of XX Cyg began in fall 2011
bull Found that XX Cygrsquos period has been reported in 8 decimal places in spring 2012
452013
5
Senior Thesis
bull Brightness variation of XX Cyg in different optical filters
bull The period of XX Cyg (using the information on brightness variation in V and R filters) and compare it with the accepted value
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
4
Motivation
bull Took Introduction to Research in fall 2010 and read about pulsation theory
bull Observed SZ Lyn a Delta Scuti star back in spring 2011
bull Found out that there exists a research group named (Delta Scuti Network) in summer of 2011
bull Scientific Observations of XX Cyg began in fall 2011
bull Found that XX Cygrsquos period has been reported in 8 decimal places in spring 2012
452013
5
Senior Thesis
bull Brightness variation of XX Cyg in different optical filters
bull The period of XX Cyg (using the information on brightness variation in V and R filters) and compare it with the accepted value
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
5
Senior Thesis
bull Brightness variation of XX Cyg in different optical filters
bull The period of XX Cyg (using the information on brightness variation in V and R filters) and compare it with the accepted value
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
6
Theory
bull SX Phoenicis star has both radial and nonradial modes of pulsation
bull Researchers predicted that the period of pulsation is slowly increasing for XX Cyg
bull Reported period 134865117 days increasing per year at 13 10-8 and theoretically increasing per year at 62 10-8
(Conidis et al 2011)
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
7
Methods
bull Data Acquisitions (a DFM engineered 16rdquo Cassegrain telescope an Apogee Alta U-series CCD Camera an Optec Intelligent Filter Wheel)
bull Getting brightness informationbull Calibrationbull Aperture photometry and Differential photometry
bull Getting period from brightness
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
8
Data Acquisitions
Date BIRV Other
08282011 All
09052011 - R
09062011 - BR
09072011 - B R
09082011 All -
09102011 All -
09142011 All -
09272011 All -
10022011 All -
10162011 All -
03212012 - RV
04032012 - R
Table 1-XX Cyg was observed in the following nights using the BIRV filters at the Paul P Feder Observatory
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
9
BiasA list of unwanted signals Cosmic rays sky light instruments CCD chips time lag on the computers
A bias frame is exposed at 0 second with the camera shutter closed
Bias frames give an idea of the read-out noise and how the computer interfere in the imaging process
A bias frame sets the pixel scales and the CCD output to the same value which helps to produce a more accurate image We subtract bias from the science images
We used the MaxIM DL 5 imaging software at the Paul P Feder Observatory The software allows us to use an inbuilt feature to take a bias frame with a zero second exposure
A master bias frame actually takes care of the incidence of the cosmic rays as it applies the mean or minmax function to the bias frames
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
10
Biasbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 000000000000000000 Exposure time in seconds
bull EXPOSURE= 000000000000000000 Exposure time in seconds
bull HISTORY Cal Master Bias 20 inputs bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after
binning) bull YPIXSZ = 90000000000000000 Pixel Height in microns (after
binning) bull SET-TEMP = -18899999618530273 CCD temperature setpoint in C
bull IMAGETYP= BIAS Type of image bull CALSTAT = M bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
bull INPUTFMT= FITS Format of file from which image was read
A calibrated Master Bias Frame
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
11
Dark A dark frame is an exposure taken with the camera shutter open but usually one needs to
blocking light from entering the camera chip
At the Paul P Feder Observatory we used the MaxIM DL 5 software to take dark frames We do not have to block light as the camera is already attached in the system
Hot pixels are defect on the CCD chip which make them to glow without direct contact to the light
A rule of thumb says one should take as many dark frames as the five times of the exposed science images
Dark frames are not scalable
The dark frame should adjust automatically But I like the idea of dark frames during the middle of the observations or taking dark frames in three intervals during the observing session
Dark current is an additive effect
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
12
Darkbull SIMPLE = T bull BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real bull NAXIS = 2 number of axes bull NAXIS1 = 3073 fastest changing axis bull NAXIS2 = 2048 next to fastest changing axis bull BSCALE = 10000000000000000 physical = BZERO +
BSCALEarray_value bull BZERO = 000000000000000000 physical = BZERO +
BSCALEarray_value bull EXPTIME = 10000000000000000 Exposure time in seconds bull EXPOSURE= 10000000000000000 Exposure time in seconds bull HISTORY Cal Master Dark 10 inputs bull SWMODIFY = MaxIm DL Version 515 Name of software that
modified the image bull HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C
bull HISTORY Exp Time 0ms) bull CALSTAT = BM bull XBINNING = 1 Binning factor in width bull YBINNING = 1 Binning factor in height bull XPIXSZ = 90000000000000000 Pixel Width in microns (after binning)
bull YPIXSZ = 90000000000000000 Pixel Height in microns (after binning)
bull SET-TEMP = -22000000000000000 CCD temperature setpoint in C
bull IMAGETYP= DARK Type of image bull PEDESTAL = -100 Correction to add for zero-based ADU bull SWOWNER = MNState Physics-9 Licensed owner of software
A calibrated Master Dark Frame
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
13
Flatbull A flat field is an exposure taken with the shutter open which basically gives us information
about the light path obstructed by the dust particles and other deformities containing inside a CCD chip
Three popular types of flat frames are 1) Dome Flats 2) Twilight and 3) Light Box flats
Flat-dark frames are separate from the dark frames which are separately taken to calibrate the science images
One should expose long enough to increase the signal to noise ratio in a flat frame
You subtract bias and dark frames from the science images Then you divide the science image by the master flat frames to complete the calibration
Star images (taken during twilight) can be eliminated using the median rejecting process
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
14
Flat
A calibrated Master Dark Frame
SIMPLE = T BITPIX = -32 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 000000000000000000 physical = BZERO + BSCALEarray_value EXPTIME = 40000000000000000 Exposure time in seconds EXPOSURE = 40000000000000000 Exposure time in seconds HISTORY Cal Master Flat(R) 10 inputs SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 0ms) CALSTAT = BDM HISTORY Dark Subtraction (Dark 4 3073 x 2048 Bin1 x 1 Temp -22C HISTORY Exp Time 4s) HISTORY Dark-Bias(Bias 13073 x 2048Bin1 x 1Temp -22CExp Time 0ms) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) SET-TEMP = -22000000000000000 CCD temperature setpoint in C IMAGETYP = FLAT Type of image FILTER = R Filter used when taking image PEDESTAL = -100 Correction to add for zero-based ADU SWOWNER = MNState Physics-9 Licensed owner of software INPUTFMT = FITS Format of file from which image was read
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
15
Final Calibrated ImageSIMPLE = T BITPIX = 16 8 unsigned int 16 amp 32 int -32 amp -64 real NAXIS = 2 number of axes NAXIS1 = 3073 fastest changing axis NAXIS2 = 2048 next to fastest changing axis BSCALE = 10000000000000000 physical = BZERO + BSCALEarray_value BZERO = 32768000000000000 physical = BZERO + BSCALEarray_value INSTRUME = Apogee Alta instrument or camera used DATE-OBS = 2011-09-15T033823 YYYY-MM-DDThhmmss observation start UT EXPTIME = 30000000000000000 Exposure time in seconds EXPOSURE = 30000000000000000 Exposure time in seconds SET-TEMP = -22000000000000000 CCD temperature setpoint in C CCD-TEMP = -22103825250000007 CCD temperature at start of exposure in C XPIXSZ = 90000000000000000 Pixel Width in microns (after binning) YPIXSZ = 90000000000000000 Pixel Height in microns (after binning) XBINNING = 1 Binning factor in width YBINNING = 1 Binning factor in height XORGSUBF = 0 Subframe X position in binned pixels YORGSUBF = 0 Subframe Y position in binned pixels FILTER = R Filter used when taking image IMAGETYP = Light Frame Type of image SITELAT = 46 52 00 Latitude of the imaging location SITELONG = 96 27 12 Longitude of the imaging location FOCALLEN = 000000000000000000 Focal length of telescope in mm APTDIA = 000000000000000000 Aperture diameter of telescope in mm APTAREA = 000000000000000000 Aperture area of telescope in mm^2 SWCREATE = MaxIm DL Version 410 Name of software that created the image SBSTDVER = SBFITSEXT Version 10 Version of SBFITSEXT standard in effect SWOWNER = MNState Physics-9 INPUTFMT = FITS Format of file from which image was read SWMODIFY = MaxIm DL Version 515 Name of software that modified the image HISTORY Bias Subtraction (Bias 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 0ms) CALSTAT = BDF HISTORY Dark Subtraction (Dark 1 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 30s) HISTORY Flat Field (Flat R 1 R 3073 x 2048 Bin1 x 1 Temp -30C HISTORY Exp Time 8s) PEDESTAL = -100 Correction to add for zero-based ADU CSTRETCH = Medium Initial display stretch mode CBLACK = 94 Initial display black level in ADUs CWHITE = 187 Initial display white level in ADUs
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
16
Aperture Photometry
bull Consists of three concentric circles
bull The innermost circle has the largest area
bull The outer two circles form an annulus which gives information about the sky glow and the background
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
17
Differential Photometry
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
18
Results Light Curve of XX Cyg Obtained in B Filter
Maximum 1151Minimum 1260
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
19
ResultsLight Curve of XX Cyg Obtained in I Filter
Maximum 1118Minimum 1170
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
20
ResultsLight Curve of XX Cyg Obtained in R Filter
Maximum 1130Minimum 1205
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
21
ResultsLight Curve of XX Cyg Obtained in V Filter
Maximum 1138Minimum 12 16
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
22
Period Analysis
bull Discrete Fourier Transformbull Peiod04 Softwarebull Time and magnitude Difference
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
23
Results Amplitude versus Frequency Plot (Only Applying the first harmonic correction)
Frequency is measured in cd
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
24
Results
bull Estimated period 1348605856 daysbull 116519546 secondsbull Accepted value 134865117 daysbull 116523461 secondsbull Account theoretical prediction for the
increasing factor 116523463 secondsbull Account reported increasing factor 116523462
seconds
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
25
Results
452013
Light Curve of XX Cyg in R filter (with my estimated Period)
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
26
Conclusions
bull Period discrepancy is 6917 secondsbull BIRV light curves have different shapesbull Would like to be consistent with aperture
photometry to improve brightness variation estimation
bull Would like to convert JD into HJD to improve period computation
bull Use the Period04 to find actual maxima minima and epoch to improve phase estimation
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
27
Acknowledgements
bull I would like to thank Dr Arne Henden (AAVSO) for providing valuable advice for analyzing the data set of XX Cyg I would also like to thank Drs Juan Cabanela Matthew Craig Linda Winkler (MSUM) for helping me with data acquisition download and analysis
bull Deanrsquos Research Grant College of Social amp Natural Sciences Fall 2010 MSUMbull I would also like to thank Dr Steve Lindaas Dr Ananda Shastri and Joy Lindell
(MSUM)bull This research work cannot be completed without active support that I received from
my peers Gregory Larson Aaron Peterson Nathan Heidt Matthew Zimney Tyler Lane Hollee Johnson LeAnn Washenberger Nicholas Weir Uchenna Ogbonnaya
bull The FM area astronomy enthusiast Doyle Heden
Find more information on my observatory log httpastronomicalobservingwordpresscom
452013
