Detector dark current
These measures are based on data from 20090521 to carry out detector noise tests. These have been separated into daytime darks and nighttime darks. The latter have the autoguider, AO etc. running and hence this can be used to test if the rms of the darks is increased when the whole system is running. There were usually two exposures at each exposure time which have been averaged before performing the stats. All averaged darks were also destriped. The first two tables here show the rms for each detector as a function of the exposure time. The first table is for the daytime darks and the second is for the night time darks. There is very little difference. The third table is the night dark table minus the day dark table and this demonstrates more quantitatively how little this difference really is.
The fourth table shows the rms of the difference of the night darks and the day darks for each detector.
Bottom line -- the autoguider etc. has little effect at all on the detector noise properties.
Daytime dark counts - detector number versus exposure time (in secs)
# 10 50 75 100 125 150 200 250 275 300
1 14.64 20.20 22.68 25.07 27.05 29.20 32.86 36.17 37.85 39.42
2 3.34 5.45 6.69 8.34 9.46 11.25 14.14 16.91 18.12 19.74
3 6.37 17.22 17.68 27.28 24.97 34.96 40.96 45.72 44.84 49.74
4 6.79 16.45 21.04 25.30 29.55 33.23 40.63 47.65 51.18 54.40
5 3.98 5.51 6.23 6.91 7.48 8.08 9.16 10.17 10.66 11.20
6 4.13 6.51 7.52 8.46 9.27 10.08 11.49 12.86 13.57 14.20
7 4.63 7.91 9.65 11.28 12.74 14.16 16.81 19.25 20.48 21.60
8 7.96 15.62 18.37 20.42 22.39 23.89 26.70 29.10 30.26 31.27
9 6.29 13.42 16.67 19.29 21.60 23.67 27.36 30.70 32.29 33.82
10 4.00 4.26 4.30 4.48 4.48 4.65 4.81 4.97 5.02 5.12
11 5.28 11.02 13.80 16.25 18.46 20.42 24.09 27.60 29.30 30.92
12 5.56 9.76 11.47 12.87 13.98 14.97 16.61 18.05 18.72 19.33
13 18.38 50.76 67.63 82.22 97.85 110.50 136.80 161.40 174.20 185.30
14 49.31 144.60 185.80 221.50 254.10 283.70 339.80 389.30 413.20 436.00
15 3.45 4.52 4.98 5.46 5.84 6.22 6.92 7.54 7.82 8.07
16 17.73 40.13 47.03 52.29 56.76 60.59 67.28 73.14 75.95 78.41
Nighttime dark counts - detector number versus exposure time (in secs)
# 10 50 75 100 125 150 200 250 275 300
1 14.49 20.15 23.25 25.13 27.70 29.42 33.22 36.72 38.33 40.03
2 3.35 5.53 7.84 8.49 10.67 11.55 14.56 17.54 18.96 20.54
3 6.14 15.85 17.59 24.89 24.32 31.96 37.23 42.09 42.50 46.55
4 6.81 16.43 21.54 25.33 29.93 33.36 40.85 47.92 51.45 54.69
5 3.99 5.50 7.32 6.94 8.46 8.14 9.25 10.35 10.83 11.33
6 4.14 6.53 8.41 8.53 10.07 10.16 11.63 13.06 13.71 14.40
7 4.65 7.96 10.60 11.37 13.55 14.29 17.01 19.46 20.64 21.79
8 7.99 15.70 19.26 20.50 23.14 24.00 26.82 29.32 30.40 31.40
9 6.26 13.41 16.94 19.21 21.85 23.64 27.34 30.71 32.31 33.80
10 4.00 4.27 5.91 4.47 6.10 4.66 4.83 5.02 5.06 5.16
11 5.32 11.10 14.31 16.36 18.93 20.55 24.28 27.79 29.52 31.13
12 5.60 9.77 12.37 12.94 14.84 15.06 16.72 18.16 18.83 19.47
13 18.30 50.45 67.09 81.66 96.57 109.60 135.70 159.90 171.90 183.20
14 49.32 144.70 185.90 221.80 254.40 284.60 340.80 390.40 414.30 437.40
15 3.47 4.56 5.93 5.50 6.72 6.31 6.96 7.62 7.87 8.15
16 17.85 40.33 47.45 52.61 57.33 61.09 67.82 73.75 76.48 78.9
Night - day
# 10 50 75 100 125 150 200 250 275 300
1 -0.15 -0.05 0.57 0.06 0.65 0.22 0.36 0.55 0.48 0.61
2 0.01 0.08 1.15 0.15 1.21 0.30 0.42 0.63 0.84 0.80
3 -0.23 -1.37 -0.09 -2.39 -0.65 -3.00 -3.73 -3.63 -2.34 -3.19
4 0.02 -0.02 0.50 0.03 0.38 0.13 0.22 0.27 0.27 0.29
5 0.01 -0.01 1.09 0.03 0.98 0.06 0.09 0.18 0.17 0.13
6 0.01 0.02 0.89 0.07 0.80 0.08 0.14 0.20 0.14 0.20
7 0.02 0.05 0.95 0.09 0.81 0.13 0.20 0.21 0.16 0.19
8 0.03 0.08 0.89 0.08 0.75 0.11 0.12 0.22 0.14 0.13
9 -0.03 -0.01 0.27 -0.08 0.25 -0.03 -0.02 0.01 0.02 -0.02
10 0.00 0.01 1.61 -0.01 1.62 0.01 0.02 0.05 0.04 0.04
11 0.04 0.08 0.51 0.11 0.47 0.13 0.19 0.19 0.22 0.21
12 0.04 0.01 0.90 0.07 0.86 0.09 0.11 0.11 0.11 0.14
13 -0.08 -0.31 -0.54 -0.56 -1.28 -0.90 -1.10 -1.50 -2.30 -2.10
14 0.01 0.10 0.10 0.30 0.30 0.90 1.00 1.10 1.10 1.40
15 0.02 0.04 0.95 0.04 0.88 0.09 0.04 0.08 0.05 0.08
16 0.12 0.20 0.42 0.32 0.57 0.50 0.54 0.61 0.53 0.58
rms difference
# 10 50 75 100 125 150 200 250 275 300
1 5.44 6.09 7.85 6.73 8.59 7.29 7.88 8.40 8.60 8.92
2 4.22 4.85 6.30 5.52 7.02 6.10 6.65 7.15 7.34 7.61
3 4.59 5.77 7.16 7.08 8.15 8.08 9.16 9.78 9.24 10.10
4 4.82 5.59 7.27 6.29 8.07 6.88 7.46 7.97 8.19 8.46
5 4.97 5.14 6.39 5.30 6.55 5.44 5.60 5.74 5.78 5.87
6 4.46 4.72 5.92 4.93 6.14 5.11 5.29 5.44 5.52 5.60
7 5.22 5.47 6.83 5.70 7.08 5.88 6.10 6.25 6.32 6.42
8 5.37 5.76 7.17 6.02 7.46 6.24 6.45 6.60 6.66 6.77
9 3.56 3.83 4.86 4.04 5.10 4.21 4.40 4.55 4.58 4.68
10 5.39 5.51 6.78 5.60 6.89 5.65 5.73 5.79 5.80 5.84
11 4.86 5.07 6.27 5.24 6.46 5.39 5.52 5.63 5.67 5.75
12 5.41 5.63 7.00 5.79 7.18 5.94 6.04 6.16 6.21 6.28
13 4.38 5.41 8.81 6.73 9.67 7.43 8.74 9.25 9.19 9.71
14 3.65 5.08 6.57 6.46 7.72 7.49 8.44 9.19 9.08 9.66
15 4.13 4.26 5.27 4.35 5.38 4.42 4.50 4.58 4.60 4.63
16 3.56 3.93 4.93 4.21 5.21 4.42 4.62 4.76 4.78 4.86