Application of charge-coupled devices for astronomical spectroscopy

Abstract

It has been found, using a charge coupled device detector and a novel on chip pre-binning technique, that qualitative high dispersion spectroscopy is possible with a small telescope and poor seeing. Using the 30 inch Coude telescope at the Royal Greenwich Observatory, an atlas of an M3 giant, HR 5490 has been obtained in a new region of the spectrum i.e. λ 9748Å - λl0153Å. However, more work is needed on the identification of the lines in order to verify this work and to extend the atlas. The readout noise of the charge coupled device camera system was found experimentally during the early stages of system development to be at most 55 electrons. Later work suggests the true figure to be closer to half this and although this is probably still greater than optimum for the device, the charge coupled device camera system has, nonetheless, demonstrated great potential as a detector for astronomical spectroscopic work particularly in the red and near infrared.