Studies and Proposals for an Automatic Crystal Control System

This document presents the status of the studies for an Automatic Crystal Control System ( ACCOS) performed since autumn 1995 for the CMS collaboration. Evaluation of a startstop method for light yield, light uniformity and decay time measurements of PbWO4 crystals is presented, as well as the first results obtained with a compact double-beam spectrophotometer for transverse transmission. Various overall schemes are proposed for an integrated set-up including crystal dimension measurement. The initial financial evaluationperformed is also given