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4.1 Introduction

The current detector is a 3072x1024 pixel custom CCD (15 pixels) fabricated through a joint program with Ford-Loral Aerospace, Steward Observatory and NOAO. The chip characteristics, as measured in the lab, include 8-9 electrons readout noise, 0.05% linearity at 80,000 electrons, and excellent CTE in both directions. The default gain is set at 2.8 electrons/ADU, DETPARS index 5, but one might consider setting it to 4.5 to cover the entire dynamic range of the chip. The chip, named F3KC and also referred to as GCAM, is thinned and AR coated. It must be UV flooded for improved sensitivity. However, it is less susceptible to losing its charge when warmed up. Although, it must be reflooded if it warms up.

Figure 8 shows the DQE of GoldCam CCD. For comparison purposes, the DQE of the old TI5 chip (no longer installed) is also shown. Additional information may be found in the CCD Characteristics Manual located in the telescope observing rooms.