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VLBA Imaging and VLBA Imaging and Polarimetry SurveyPolarimetry Survey
Greg Taylor (UNM)
The Future of the VLBA – Charlottesville, VA Jan. 28, 2011
The VIPS team is:
Greg Taylor (UNM/NRAO), Chris Fassnacht (UCD), Joe Helmboldt (UNM), Larry Weintraub (Caltech)Jim Ulvestad (NRAO), Craig Walker (NRAO), Steve Myers (NRAO), Lorant Sjouwerman (NRAO), Tim Pearson (Caltech), Tony Readhead (Caltech), Neil Gehrels (NASA GSFC), Roger Romani (Stanford), Peter Michelson (Stanford), Roger Blandford (KIPAC)
PhD Students:
Steve Tremblay (UNM) anticipated 2011 Justin Linford (UNM) anticipated 2012
VIPS and Fermi
VLBA Imaging Polarimetry Survey (VIPS)• 1127 sources: S > 85 mJy, dec > 20, |b|>10 at 8 GHz in SDSS northern cap• First epoch observations during 200+ hours on VLBA in 2006 (~$30K Funding from Stanford/UNM for disks)• Identifications and redshifts from SLOAN, HET, Palomar, …• Goals: - Characterize Fermi sources - Understand polarization properties of AGN classes - Study AGN environments
- Find close binary black hole systemshttp://www.phys.unm.edu/~gbtaylor/VIPS/
VIPS on the web1127 in sample 11 not detected 169 previously imaged------947 newly imaged
http://www.phys.unm.edu/~gbtaylor/VIPS/
PublicationsPublications Taylor et al. 2005, ApJS, "An Automated Taylor et al. 2005, ApJS, "An Automated
approach...approach... Helmboldt et al. 2007, ApJ, "VIPS at 5 GHz"Helmboldt et al. 2007, ApJ, "VIPS at 5 GHz" Taylor et al. 2007, ApJ, "Characteristics of Taylor et al. 2007, ApJ, "Characteristics of
EGRET ...EGRET ... Tremblay et al. 2008, ApJ, "A Shrinking CSO ...Tremblay et al. 2008, ApJ, "A Shrinking CSO ... Helmboldt et al. 2008, ApJ, "A statistical Helmboldt et al. 2008, ApJ, "A statistical
description...description... Tremblay et al. 2009, ApJ, "Identifying CSOs ...Tremblay et al. 2009, ApJ, "Identifying CSOs ... Linford et al. 2011, ApJ, "Characteristics of Linford et al. 2011, ApJ, "Characteristics of
Fermi ...Fermi ...
+ 7 more by the VIPS collaboration+ 7 more by the VIPS collaboration
>12 more by others>12 more by others
VIPS CSO Candidates
Follow-up Observations• 5, 8, 15 GHz VLBA• Full polarization
Spectral classification: F
Kinematic Analysis Ages/Dynamics
Polarization Analysis
Evolution of Radio Galaxies
Tremblay et al in prep.
20 pc
CSO 'Age' Histogram
0
0.5
1
1.5
2
2.5
3
3.5
500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000
Age (years)
Number
Age Estimates
Gugliucci et al. 2005
Tremblay et al in prep.
Core Brightness Core Brightness TemperaturesTemperatures
LAT core TLAT core TBBs tend s tend to be higher than to be higher than non-LAT. Except non-LAT. Except BL Lacs.BL Lacs.
Kolmogorov-Kolmogorov-Smirnov (K-S) Smirnov (K-S) tests indicate that tests indicate that the FSRQs are the FSRQs are very different, but very different, but BL Lacs are BL Lacs are similar.similar.
Stacked histogramsTop: LATBottom: non-LAT
Linford et al.
Core Polarization Core Polarization
The The percentage of percentage of sources found sources found to be to be polarized is polarized is higher for LAT higher for LAT blazars than blazars than for non-LAT for non-LAT blazars.blazars.
CJF 0402+379 – A Compact Binary CJF 0402+379 – A Compact Binary Black Hole Black Hole Radio Continuum Rodriguez et al. Radio Continuum Rodriguez et al. astro-ph/0604042astro-ph/0604042
Naturally weighted 2005 VLBA imagesNaturally weighted 2005 VLBA imagesof 0402+379 at 0.3, 5, 8, 15, 22, and 43 GHz. of 0402+379 at 0.3, 5, 8, 15, 22, and 43 GHz.
C1: 0.183 ± 0.048 C1: 0.183 ± 0.048 pc pc
C2: 0.124 ± 0.035 C2: 0.124 ± 0.035 pc pc Projected Projected separation separation between C1 and between C1 and C2 equal to 7.3 pcC2 equal to 7.3 pc
J16325+3547J16325+3547
J17246+6055J17246+6055
Thoughts about the Thoughts about the FutureFuture
Don't sacrifice the User communityDon't sacrifice the User community They contribute ideas, effort and (sometimes) They contribute ideas, effort and (sometimes)
fundsfunds Maintain time for Users on the VLBAMaintain time for Users on the VLBA Maintain 10 antennas if at all possibleMaintain 10 antennas if at all possibleFuture plans Future plans Take advantage of bandwidth expansion to do Take advantage of bandwidth expansion to do
polarimetry of gamma-ray blazars (RM Synthesis)polarimetry of gamma-ray blazars (RM Synthesis) Contemporaneous VLBA observations with Fermi Contemporaneous VLBA observations with Fermi Study CSO Motions, spectra, Faraday RMs, agesStudy CSO Motions, spectra, Faraday RMs, ages Use new correlator to survey 10,000+ sources for Use new correlator to survey 10,000+ sources for
SBBHs SBBHs Difficult to do above with < 9 antennas (reduced Difficult to do above with < 9 antennas (reduced
spatial dynamic range, fidelity)spatial dynamic range, fidelity)
Backup SlidesBackup Slides
Radio Target ListRadio Target List Selection SSelection S4.84.8>65mJy, |b|>10>65mJy, |b|>1000, , <0.5 -- CLASS+<0.5 -- CLASS+
11,131 sources - Healey et al. 200711,131 sources - Healey et al. 2007 Attempts to fill in PMN holes w/ S5, lower Attempts to fill in PMN holes w/ S5, lower -selected sources-selected sources CCombined ombined RRadio adio AAll-sky ll-sky TTargetted argetted EEight-GHz ight-GHz SSurvey: urvey:
CRATESCRATES
Sky Coverage
VIPS 5 GHzVIPS 5 GHzSummary of Source Types in VIPSSummary of Source Types in VIPSType Type N N Npol/N Npol/N PS PS 276 276 31+/- 4% 31+/- 4% SJET SJET 241 241 36 +/- 5% 36 +/- 5% LJET LJET 471 471 41 +/- 4% 41 +/- 4% CSO CSO 103 103 15 +/- 4% 15 +/- 4% CPLX CPLX 17 17 11 +/- 8% 11 +/- 8% ND ND 11 11 ……
Helmboldt et al. 2007
At their base, Jets tend to have magnetic fields aligned with the jet axis.
This trend should become more pronounced once we can correct for Faraday rotation
Which one of these Jets will be Which one of these Jets will be detected by GLAST?detected by GLAST?
Helmboldt et al. 2007
Manpower EstimatesManpower EstimatesFirst epoch 5 GHz - Kept upFirst epoch 5 GHz - Kept up 2 x 10 hours each month for 10 months2 x 10 hours each month for 10 months 50% of Joe H., 10% of Greg, 5% Lorant50% of Joe H., 10% of Greg, 5% Lorant
SBBH 5, 8, 15 GHz - not keeping up SBBH 5, 8, 15 GHz - not keeping up 3 x 17 hours in the past 3 months3 x 17 hours in the past 3 months 50% of Steve T., 10% of Greg50% of Steve T., 10% of Greg Reduction is more complicatedReduction is more complicated
Proposed Multi-epoch follow-up (20 Proposed Multi-epoch follow-up (20 h/month)h/month)
1.5 FTE, 10% of Greg, 5% Lorant1.5 FTE, 10% of Greg, 5% Lorant
In both hotspots of the In both hotspots of the source, N2 and S2, a source, N2 and S2, a steep spectrum was steep spectrum was found.found.
For both central For both central components, C1 and C2, components, C1 and C2, the spectrum peaks at the spectrum peaks at ~10 GHz. ~10 GHz.
Spectral index distribution between 8 andSpectral index distribution between 8 and22 GHz from the 2005 VLBA observations. 22 GHz from the 2005 VLBA observations.
CJF 0402+379CJF 0402+379