Radiation safety analysis for the experimental hutches at the Linac coherent light source at SLAC

The Linac Coherent Light Source (LCLS), the worldʹs first X-ray free electron laser, will be constructed at the Stanford Linear Accelerator Center (SLAC) and is expected to be completed in 2009. A two-mirror system will be used in order to reduce background radiation in near and far experimental hutches. This paper describes the layout of the two-mirror system and also reports on the shielding requirements for the experimental hutches. Two beam loss scenarios for radiation sources are discussed: losses from the high energy electron beam hitting beam components and X-rays produced in the 130 m long undulator and scattered on X-ray mirrors. The FLUKA Monte-Carlo particle transport code was used for the shielding design and for the determination of the radiation levels around the experimental hutches.