CCD test data for 16 channel mode

Report, 2002-05-17 (brief)

 

Full frame, unbinned, dual redout:

CCD (1) 1a 1b 2a 2b 3a 3b 4a 4b
FITS section 1 2 3 4 5 6 7 8
Gain (e-/ADU)
09 Nov
2009 (2)
2.7 2.8 2.7 2.3 2.8 2.5 N/A 2.3
 
Read noise (e-)
09 Nov
2009 (3)
6.7 12.8 7.0 5.2 8.4 7.2 N/A 5.6
                 
Non-
linearities
17 May
2002 (4)
~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<0.8% ~<1%
Non-
linearities
Oct 2005 (4)
~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1%
                 
Spurious charge (ADU)
17 May
2002 (5)
N/M ~10 ~5 ~8 ~10 ~12 ~15 ~8
                 
Full well (e-)
08 May 2004 (6)
130,000 125,000 91,000 87,000 77,000 81,000 70,000 71,000
Full well (e-)
Oct 2005 (7)
>112,000 >118,000 86,000 89,000 87,000 97,000 67,000 67,000

 

CCD (1) 5b 5a 6b 6a 7b 7a 8b 8a
FITS section 9 10 11 12 13 14 15 16
Gain (e-/ADU)
09 Nov
2009 (2)
2.3 2.3 2.6 2.6 2.1 2.2 2.7 2.7
                 
Read noise (e-)
09 Nov
2009 (3)
6.4 6.2 15.2 7.3 7.9 12.0 10.4 8.7
                 
Non-
linearities
17 May
2002 (4)
~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1%
Non-
linearities
Oct 2005 (4)
~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1% ~<1%
                 
Spurious charge (ADU)
17 May
2002 (5)
~-5 ~-5 ~-5 ~-5 ~-2 ~-2 ~-5 ~-5
                 
Full well (e-)
08 May 2004 (6)
76,300 84,000 97,000 102,000 95,500 93,000 62,000 67,600
Full well (e-)
Oct 2005 (7)
76,000 80,000 73,000 81,000 91,500 100,000 56,000 61,000

 

Notes:

1. When looking at a Mosaic image, the 8 lower segments are denoted from left to right (ccd,amp) 1a,1b,2a,2b,3a,3b,4a,4b. Across the top, from left to right: 5b,5a,6b,6a,7b,7a,8b,8a (see plot below).


2. Gain measured from Transfer curve.


3. Read noise calculated from standard deviation of a bias frame × gain.


4. Nonlinearities are the width of the envelope of the count rate curve over a large part of the dynamic range of the detector. They include any variation in the light source and shutter effects, although the shutter delay has been removed to first order. These measurements are therefore an upper bound.


5. Spurious charge is charge that is injected into the CCD as a result of parallel clocking. It shows up as a slope in the bias level in the vertical direction, quoted here in ADUs from the top to the bottom of the unbinned image.


6. Measured in the La Serena lab after the installation of a new CCD #3. Full well was determined from the variance curve, noise from the overscan.


7. Measured in situ at Blanco prime focus, using flat field lights.