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Introduction

This document describes the performance of the W19-(0,0) CCD, installed in a cryostat specifically for the ALFOSC, as measured in the laboratory of Copenhagen University Observatory. The CCD was tested using the controller that will also be used when the camera is commissioned on the ALFOSC, so the test results are expected to be very close to what is found under observing conditions. A few data obtained during commissioning at the NOT are also included.

The CCD is a Ford-Loral three side buttable with 2048 imaging pixels, each square. Packaging for back-side illumination, ``ultra-thinning'' and coating was performed by the Steward Observatory CCD Laboratory. The CCD is anti-reflection coated using HfO for maximum QE around 475nm, and for high blue QE it has a ``Cat-C'' coating that has proved practically maintenance-free. The CCD is intended to replace the previous ALFOSC CCD, that required UV-flooding for good blue QE, but did not deliver stable sensitivity. All tests at CUO indicate that this problem will be eliminated with the new CCD.



Tim Abbott
Mon Apr 12 17:00:34 ACT 1999