National Synchrotron Light Source (NSLS): An Optimized Source for Synchrotron Radiation

Abstract

• 'l4 I I \ ~ q .--~ Synchrotron radiation has a number of special characteristics that make electron storage rings and synchrotrons powerful tools for research with photons . Appl ications in both basic research and technology are possible and there are exciting pr ospects for the future with the design and construction of electron storage rings dedicated to synchrotron radiation production. Synchrotron radiation has a continuous spectrum ranging from the infrared to X-ray wavelengths. It is both intense and strongl y polarized in the plane of the electron orbit. The light is emitted in pulses that are typica lly I X I o-9 sec long and have repetition frequencies of the order of 1 X 10 6 pulses per secon d. With the current designs, beam cross sections of 1 mm 2 or less can be ach ieved and the photons are sharply collimated in a narrow cone about the tangent to the orbit of the emitting particle.Since the first sustained research program with synchrotron light began in 1961 art the National Bureau of Standards utilizing a 180 MeV electron ring, all the research programs world wide have used machines that have been designed for other purposes , high energy physics in particular. Realizing that with an optimized electron storage ring the future research with synchrotron light could be even brigh ter, a number of countries have proposed and started construction of dedicated facilities in the 1970 ' s. In the sections that follow some of the considerations for an optimal design of a storage ri ng will be outlined and the choices of parameters for the Nati onal Synchrotron Light Source (NSLS) at Brookhaven National Laboratory (BNL) will be presented . Also the policy for utilization of NSLS beam lines will be described for both the 0. 7 Ge V ( VUV) storage ring and the 2.5 GeV (X-ray) storage ring.