24um Read Noise Log

The following table contains read noise and dark current measurements from dark exposures taken during LBTC and CTA tests. For RAW data, slopes were fit for each pixel in each DCE from a weighted average of slope segments between each read, correcting for cosmic ray hits. For both RAW and SUR data, slopes were then converted to total counts in electrons. The standard deviation of the counts for each pixel from a line fit over all DCEs in a given exposure was computed, ignoring the first DCE (where the counts are significantly lower due to the first reset/sample frame). The shot noise expected from the total counts is then removed from this standard deviation; the resulting read noise is then the average over the array, rejecting the top 1% pixel values. The dark current is simply the average signal in electrons/second. Note that in many cases the array is not completely in the dark; for example, some of the darks were taken immediately after stim exposures, and contain small latent signal. Also, the darks measured here were not all taken at the internal dark scan mirror position (see "Scanabs"). Quoted errors are the standard deviation of the dark current and read noise over the bottom 99% of the pixels.

Date	Filename	CE	Temp (K)	Exp. time (s)	# DCEs	Mode	D.C. (e/s)	Err.	Rd. noise (e)	Err.	Comments	Scanabs
LBTC:							(bottom 99% pix)		(bottom 99% pix)
1/31/00	2000-031T21.29.34_A24	1	4	3	50	SUR	3.6	13.7	110.4	24.3		857
	2000-031T21.34.04_A24	1	4	10	50	SUR	2.4	3.1	43	6.4		857

2/8/00	2000-039T16.41.42_A24	1	4	3	50	SUR	2.4	6.1	93.1	13.8		857

2/18/00	2000-049T19.33.31_A24	1	4	3	50	SUR	2.1	14	108.6	23.7		700
	2000-049T19.39.10_A24	1	4	10	50	SUR	1.9	1.8	40.1	7		700

2/14/00	mips_2000-045T16.39.39.806_0_A24	1	4	30	50	RAW	11.3	2	32.3	7.4	Some residual latent decay	700
	mips_2000-045T17.34.12.467_0_A24	1	4	3	50	SUR	1.5	7	93.9	16.1		2007
	mips_2000-045T17.38.14.305_0_A24	1	4	10	50	SUR	2	2	39.5	6.9		2007
	mips_2000-045T21.24.07.530_0_A24	1	4.5	3	50	SUR	21.3	7.5	99	12.1	Glitch in DCE 10	2007

2/15/00	mips_2000-046T14.39.25.619_0_A24	1	5	30	50	RAW	15.6	3.1	40.5	7.4	Some residual latent decay	700
	mips_2000-046T15.30.13.902_0_A24	1	5	3	50	SUR	10.6	16.5	86.3	11.5		2007
	mips_2000-046T15.33.41.762_0_A24	1	5	10	50	SUR	5.3	6.7	49.9	4.3		2007
	mips_2000-046T16.32.09.769_0_A24	1	5.3	30	50	RAW	7.8	1.7	32	6.2	Very small latent decay (~0.5e/s over 50 DCEs)	700
	mips_2000-046T17.21.22.811_0_A24	1	5.3	3	50	SUR	9.2	20.3	94	16.5		2007
	mips_2000-046T17.24.48.907_0_A24	1	5.3	10	50	SUR	3.3	5.4	48.5	8.1		2007

3/13/00	2000-073T19.09.43_A24	2	5	3	50	SUR	11	5.2	92.2	14.7	last few DCEs vary wildly (glitch?)	697
	2000-073T19.24.08_A24	2	5	10	50	SUR	9.2	8.4	46.5	6.1		697

4/27/00	2000-118T23.19.09_A24	?	5	10	50	SUR	18	9	59.2	11.3	first unrejected DCE ~50% lower than the rest	753

CTA:
12/14/00	mips_2000-349T21.34.57.104_0_A24	1	5	10	50	SUR	11.5	8.1	43.5	13		694
12/16/00	mips_2000-351T20.42.01.682_0_A24	1	5	3	50	SUR	34.1	28.3	57.4	7.2		694
	mips_2000-351T20.45.43.610_0_A24	1	5	10	50	SUR	12.2	8.8	44.4	6.5		694
	mips_2000-351T20.55.47.073_0_A24	1	5	30	50	SUR	9.2	6.9	32.5	44	most pixels ~0	694
	mips_2000-352T00.31.41.852_0_A24	1	5	10	10	RAW	11.1	9.2	34.1	14		2042
	mips_2000-352T00.39.17.484_0_A24	1	5	10	10	RAW	46.8	8.6	25.9	13.6	Contains latent signal from flat in prev. exposure	2042
	mips_2000-352T00.41.10.428_0_A24	1	5	10	10	SUR	17.2	9.7	37.2	15.9		2042
	mips_2000-352T00.48.48.174_0_A24	1	5	10	10	SUR	16.6	9.7	38.6	15.8		2042
	mips_2000-352T01.30.49.191_0_A24	1	5	10	10	RAW	11.3	8.6	34.8	17.3		2042
	mips_2000-352T01.40.17.305_0_A24	1	5	10	10	SUR	14.9	9.3	41.2	14.3		2042

3/22/01	mips_2001-081T23.47.11.115_0_A24	2	5.1	10	50	SUR	12.9	8.9	46.4	9.1		694

3/24/01	mips_2001-083T23.10.33.021_0_A24	2	5.1	10	20	SUR	17.3	10.6	47.7	9		2042
	mips_2001-083T23.06.37.893_0_A24	2	5.1	10	20	RAW	22.1	9.3	45.8	31.3		2042