FRONT END DESIGNS FOR THE 7-GEV ADVANCED PHOTON SOURCE

The conceptual designs for the insertion device (ID) and bending magnet (BM) front ends have been completed for the 7 GeV Advanced Photon Source (APS) under construction at Argonne National Laboratory. These designs satisfy the generic front end functions. However, the high power and high heat fluxes imposed by the X-ray sources of the 7 GeV APS have presented various design engineering challenges for the front end. Consideration of such challenges and their solutions have led to novel and advanced features including modularized systems, enhanced heat transfer concepts in the fixed mask and the photon shutter designs, a radiation safety philosophy based on multiple photon shutters for a fail-safe operation, a submicron resolution beam position monitor for beam monitoring and ring feedback information, and minimal beam filtering concepts to deliver maximized beam power and spectra to the experimenters. The criteria and special features of the front end design are discussed in this paper.