Detector upgrade for FLAMES: GIRAFFE gets red eyes

摘要

GIRAFFE is an intermediate resolution spectrograph covering a wavelength range from 360-930nm and fed by optical fibers as a part of FLAMES, the multi-object fiber facility mounted at the ESO VLT Kueyen. For some time we sought a new detector for GIRAFFE spectrograph to boost the instrument's red QE (Quantum Efficiency) capabilities, while still retaining very good blue response. We aimed also at reducing the strong fringing present in the red spectra. The adopted solution was an e2v custom 2-layer AR (Anti-Reflection) coated Deep Depletion CCD44-82 CCD. This device was made in a new e2v Technologies AR coating plant and delivered to ESO in mid 2007 with performance that matches predictions. The new CCD was commissioned in May 2008. Here we report on the results.