ULTRASAT: Imaging Properties of Delta-Doped CCDs

Purpose

Test the imaging properties of delta-doped CCDs.
Note that the Delta-doped CCDs are mounted next to the state-of-the-art
commercial e2V detector. This eases comparative studies.

In detail

1. Imaging quality: QE on sky
2. Compare performance in QE in U,B, V bands relative to E2V.
3. Determine limitations to flat field by using dome flat field data
4. Determine ability to make the faintest image (“sky flat”)
5. Astrometric precision and stability
6. Stability of imaging attributes (changes in QE, hot pixel
   growth, etc)

Image Credit: Palomar Observatory

In each case, the E2V chip provides the comparison for truly on sky tests.

1. Commission WASP (with E2V and Delta-doped side-by-side).
   December run has been scrapped and commissioning has been
   rescheduled to late January 2016.
2. Undertake comparative QE studies (on sky) with both detectors (same
   weather conditions)
3. Evaluate photometric & astrometric stability (delta-doped should not
   affect long term behaviour but some issues were raised by a referee
   in regard to TRL rating for ULTRASAT)

This will take with at least 3 and hopefully 6 runs in 2016B (we will
propose time).

The KISS project consists of the following goals:

1. Imaging quality: QE on sky in various bands (relative to commercial E2V)
2. Astrometric precision and stability
3. Stability of imaging attributes (changes in QE, hot pixel growth, etc.)

The first step is to
test the WASP cryostat (which is
built to accommodate both the JPL supplied delta-doped CCDs and a commercial e2V detector)
and goes behind the prime focus imaging camera. The second step is
to mount the delta-doped CCD and undertake a commissioning run at Palomar (goal 1)
The final step are several runs for long term characterization (goals 2 and 3).