<title>Status of the Advanced Light Source</title>

Abstract

Status of the Advanced Light SourceJ. N. MarxAccelerator & Fusion Research Division, Lawrence Berkeley Laboratory1 Cyclotron Road, Berkeley, CA 94720ABSTRACTThe Advanced Light Source (ALS), now under construction at the Lawrence Berkeley Laboratory, will be a national user facil-ity for the production ofhigh-brightness and partially coherent soft x-ray and ultraviolet synchrotron radiation. The ALS is basedon a low-emittance electron storage ring optimized for operation at 1.5 GeV with insertion devices in 10 long straight sectionsand 24 premier bend-magnet ports. High-brightness photon beams, from less than 10 eV to more than 2 keY, will be producedby undulators, thereby providing many research opportunities in materials and surface science, biology, atomic physics andchemistry. Wigglers and bend magnets will provide high-flux, broad-band radiation at energies to 10 keY.2. INTRODUCTIONThe availability of intense, tunable, collimated, polarized radiation in the x-ray and ultraviolet regions of the spectrum hasdriven theevolutionary developmentofdedicated facilities optimized forthe generation ofsynchrotron radiation [1]. The newest,third-generation synchrotron sources are based on the use ofan electron or positron storage ring specifically designed to have avery low emittance and many long straight sections containing insertion devices (wigglers and undulators).The combination ofa low-emittance storage ring with optimized undulators makes possible the generation ofradiation witha spectral brightness that is increased by orders ofmagnitude over that ofexisting, second-generation sources. In the past, order-of-magnitude increases in brightness have led to qualitatively new developments in spectroscopic and structural studies of bothgas-phase and condensed matter. The increased brightness of the third-generation synchrotron sources is expected to have asimilar impact [2, 3].Around the world, construction ofseveralthird-generation synchrotron sources is either under way orplanned, including theAdvanced Light Source (ALS) at the Lawrence Berkeley Laboratory. The ALS is in its fourth year of construction with a totalconstruction cost of approximately $