The LBL ADVANCED LIGHT SOURCE*

The LBL Advanced Light Source (ALS) will be a third generation synchrotron radiation facility. It is based on a low emittance 1-2 GeV electron storage ring (natural radial emittance < 10 nm-rad), optimized to produce extremely bright beams of electromagnetic radiation (in the energy range from a few eV to around one keV) from insertion devices known as undulators. The storage ring is fed from an injection system consisting of a 50 MeV linac and a 1.5 GeV, 1 Hz, booster synchrotron, which can fill the ring to its nominal onerating current (400 mA, multibunch, or 7.6 &, single bunch) in a feiminutes. ‘ As weli as high brightness (which is a consequence of the very small electron beam emittance in the storage ring), the design emphasizes: picosecond time structure, laserlike coherence properties, narrow bandwidth, and long beam lifetimes. The more familiar continuous synchrotron radiation spectrum will be available from bending magnets and from wiggler magnets. This paper gives a general description of the ALS and discusses some of the significant design issues associated with the low emittance storage ring that is required for this new facility