Summary of MD02.refstack.20120827

Similar to the MD02.GR0 (MD.GR0) refstacks for the 2011/2012 season, these include recent improvement and input cuts to help constrain the convolved stacks as well. Because the refstack is made with reprocessed pixels, the refstack pixels will now have the ubercalibration.

MD02 observations started Sept. 27 (ended last season started mid-Sept. and ended of February).

Filter	N total	N (FWHM<8 pixels)
g	331	260
r	327	281
i	427	386
z	509	483
y	386	340

MD02.V3 Processing

Exposure reprocessing was done for only a limited number (~150) from 2010+2011 to provide a balance of N input warps versus best seeing, excluding exposures with large background, low zeropoints and large elongation. Processing chip-warp and the refstack itself has the same label, data_group

• label: MD02.refstack.20120927 --> once on as active refstack for diffims, label will change to MD02.refstack
• data_group: MD02.refstack.20120927

Histograms of the FWHM major and minor and elongation from camera stage value (full exposure) for the sample of reprocessed exposures (red) and used for refstack.20120927 (top blue) and used for refstack.2011 (bottom blue).

Test stack (reftest) sample also made again for skycell.055 with different number of input warps. Found skycell.055 may not be a good indicator of FWHM with different number of inputs, also did sample for skycell.033.

• label: MD02.reftest.20120927
• data_group:
  • MD02.reftest.20120927.c#f<FWHM cut> where #=comparison run, <FWHM cut>=cut <fwhm_major from camProcessedExp
  • MD02.reftest.20120927.all.<FWHM cut> where all means 2009+2010+2011 data possible, <FWHM cut>=cut <fwhm_major from camProcessedExp
  • MD02.reftest.20120927.2011.<FWHM cut> where 2011 means 2011 data only, <FWHM cut>=cut <fwhm_major from camProcessedExp

Summary comparison table with the approximate FWHM (major) as the PSF FWHM from a center field skycell (V3=055) after running psphot on the stacks. Because the reftests were all run on the same date, the stack_id is important to note to separate by filter as well.

version data_group (stack_id)	filter	center skycell.055 input warps (rej)	center skycell.055 FWHM (major pixels)	skycell.033 input warps (rej)	skycell.033 FWHM (major pixels)
new MD02.refstack.20120927	g	()		()	"
MD02.reftest.20120927.all.55 (1503420)	g	79(31)	5.52	79(24)	4.49
MD02.reftest.20120927.2011.55 (1503421)	g	41(15)	5.36	41(8)	4.47
MD02.reftest.20120927.c1f52 (1505150)	g	37(10)	5.56	37(12)	4.37
MD02.reftest.20120927.c1f54 (1505151)	g	61(20)	5.49	61(19)	4.43
MD02.reftest.20120927.c1f61 (1505152)	g	93(37)	5.54	93(24)	4.54
MD02.reftest.20120927.c1f62 (1505153)	g	104(47)	5.33	104(28)	4.58
old MD02.refstack.20110907	g	64(6)	5.28	64(4)	4.68
new MD02.refstack.20120927	r	()	"	()	"
MD02.reftest.20120927.all.49 ()	r	88(20)	4.96	88(24)	4.06
MD02.reftest.20120927.2011.49 ()	r	50(15)	4,91	50(12)	4.07
MD02.reftest.20120927.c1f 45 ()	r	36(8)	4.79	36(7)	3.97
MD02.reftest.20120927.c1f47 ()	r	63(11)	4.87	63(17)	4.01
MD02.reftest.20120927.c1f51 ()	r	89(20)	4.93	89(20)	4.09
MD02.reftest.20120927.c1f58 ()	r	118(34)	5.02	118(37)	4.15
old MD02.refstack.20110907	r	63(6)	4.6	63(5)	4.19
new MD02.refstack.20120927	i	()	"	()	"
MD02.reftest.20120927.all.45 ()	i	89(21)	4.31	89(23)	3.81
MD02.reftest.20120927.2011.45 ()	i	40(12)	3.71	40(10)	3.75
MD02.reftest.20120927.c1f41 ()	i	34(7)	4.26	34(9)	3.70
MD02.reftest.20120927.c1f43 ()	i	54(9)	4.33	54(13)	3.80
MD02.reftest.20120927.c1f48 ()	i	92(27)	4.43	92(27)	3.88
MD02.reftest.20120927.c1f52 ()	i	121(23)	4.47	121(35)	3.96
old MD02.refstack.20110907	i	61(2)	4.0	61(1)	3.99
new MD02.refstack.20120927	z	()	"	()	"
MD02.reftest.20120927.all.41 ()	z	91(28)	3.78	91(23)	3.63
MD02.reftest.20120927.2011.41 ()	z	40(10)	3.70	40(8)	3.67
MD02.reftest.20120927.c1f38 ()	z	25(7)	3.54	25(5)	3.37
MD02.reftest.20120927.c1f40 ()	z	58(20)	3.87	58(12)	3.55
MD02.reftest.20120927.c1f42 ()	z	92(22)	3.85	92(26)	3.64
MD02.reftest.20120927.c1f45 ()	z	116(27)	3.90	116(22)	3.70
old MD02.refstack.20110907	z	67(5)	3.6	67(2)	3.75
new MD02.refstack.20120927	y	()	"	()	"
MD02.reftest.20120927.all.41 ()	y	95(29)	3.60	95(18)	3.48
MD02.reftest.20120927.2011.41 ()	y	86(16)	3.60	86(27)	3.44
MD02.reftest.20120927.c1f38 ()	y	35(5)	3.52	35(8)	3.35
MD02.reftest.20120927.c1f39 ()	y	61(11)	3.57	61(8)	3.43
MD02.reftest.20120927.c1f42 ()	y	96(21)	3.62	96(23)	3.51
MD02.reftest.20120927.c1f46 ()	y	118(25)	3.64	118(38)	3.51
old MD02.refstack.20110907	y	58(3)	4.04	58(2)	4.38

The center skycell often has a problem with worse seeing so added skycell.033 for comparison. Overall very little improvement in FWHM is possible (~0.2 pixels with minimum number of inputs as with other fields), but now depth is similar with other MD.

Problems

• convolved stacks have strange PSF -- skycells X,Y : reprocessed using DEEP_STACK config and may not have best FWHM, but on the edge of field so won't anyways.
• bad cell arc in y-band --

• bad cell arc in g-band and less so in other filters --

Refstack Summary Plots

Source photometry psf_major,_minor maps (grizy):

Magnitude of sources@5-sigma maps (grizy):

Detection efficiency magnitude @50% recovery (500 fakes, grizy):