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CCD Characteristics

The detector is a 2048x2048 pixel SITe (formerly Tektronix) thinned CCD with good UV response. Another CCD can be mounted at the direct imaging position, although the standard Palomar CCD dewar sizes results in the guider being impossible to focus simultaneously with the CCD. (A spacer plate could be constructed to allow for simultaneous focusing.) As the current COSMIC CCD has high quantum efficiency across the entire optical window (see Figure 1), there might be nothing to be gained by using a different CCD. The characteristics of this CCD are given in Table 3.


Table 3
COSMIC CCD Characteristics
Pixel size 24 um
Array size 2048x2048 pixels
Peak QE ( nm) ~88%
Read Noise 12 e-
Gain 3.1 e- / DN
Time to Readout 149 seconds (no binning)
  29 seconds (SNAP, 4x4 binning)
Orientation, imaging (base PA=180 )
With Spectrograph Tower
N down, E left (display ccd001 1)
N up, E left (display ccd001[*,-*] 1)
Orientation, spectroscopy (base PA=180)
With Spectrograph Tower
E left, blue down (display ccd001 1)
E left, blue up (display ccd001[*,-*] 1)
Orientation, imaging (base PA=180 )
Direct Imaging
N up, E right (display ccd001 1)
Overscan pixels x = 2038:2048
Dark current unknown
Bias 200<bias<275 DN
Minimum t_exp (photometry) 2 seconds



next up previous
Next: Starting Up the COSMIC Up: Introduction Previous: Reimaged Mode
Roy Gal
4/25/1998