FourStar Commissioning

Events

1. Sept 5, 2012 telecon – SAC signed off on the instrument itself. 2. Wendy has since OK’d waiver of original requirement of a

pipeline, i.e., Dan’s.

3. Now we ask that the SAC officially waive the requirement and pass this recommendation along to the Council.

4. The Council then (hopefully) declares it commissioned.

Meanwhile …

Two pipelines now “exist”:1. Dan’s – good for final or near-final data products, at the telescope; runs automatically as the data flow in. Probably not too easy to get working at a home institution, but this remains to be seen. Written in Python.

2. Andy Monson’s – hands-on, can be run at the telescope, but not automated as Dan’s is. Somewhat more general, and can be run elsewhere with a little help from Andy. Written in

shell scripts calling IRAF routines.

Typical result of Dan’s

Some parameters: 1% filter at 1.18 microns 7 hour exposure 105 x 240 sec individual frames 2.5 pixels FWHM on final stacked image Depth is as advertised in online manual Note chip seams: gone; note increased noise Wavelet transform method for sky creation; yields very flat

background

Cosmos field

Pipeline diagnostics page: shifts, phot offsets, # of stars, FWHM

Thumbnails: current stack, coverage map, noise map

Thumbnails: sky-subtracted frames

47 Tuc example of wavelet method for sky

1. 2 minutes at Ks total2. 3.5 pix FWHM3. Main thing to notice is how flat sky is even in the presence of an extreme background gradient.