High-Energy gamma-Ray BEAMS from Compton-Backscattered Laser Light

摘要

Collisions of light photons with relativistic electrons have previously been used to produce polarized gamma -ray beams with modest (-10%) resolution but relatively low intensity. In contrast, the LEGS project (Laser + Electron Gamma Source) at Brookhaven will produce a very high flux (>2 x 10 exp 7 s exp -1 ) of background-free polarized gamma rays whose energy will be determined to a high accuracy ( delta E = 2.3 MeV). Initially, 300(420)-MeV gamma rays will be produced by backscattering uv light from the new 2.5(3.0)-GeV X-ray storage ring of the National Synchrotron Light Source (NSLS). The LEGS facility will operate as one of many passive users of the NSLS. In a later stage of the project, a Free Electron Laser is expectred to extend the gamma -ray energy up to 700 MeV. (ERA citation 08:030220)