SOME FUNDAMENTALS OF COOLED MIRRORS FOR SYNCHROTRON-RADIATION BEAM LINES

We present an analysis using conventional heat-transfer theory of a co mmon type of synchrotron-radiation-beam-line mirror with rectangular c ooling channels. The analysis leads to a simple analytic expression fo r the slope error, which enables the distortion performance to be esti mated in practical situations. It also provides an understanding of th e effect of the various parameters on the goodness of the cooling proc ess and an insight into the underlying physics. The analysis is applie d to determining the design steps needed to achieve low slope errors a nd/or high-heat-removal rates with this type of mirror. The slope-erro r performance of various materials in a specific design are compared a nd the best performance is obtained from (in order) invar, silicon, an d silicon carbide. (C) 1996 Society of Photo-Optical instrumentation E ngineers.