Radiation protection in the NLC test accelerator at SLAC

Abstract

This report describes the ionizing radiation protection and safety issues in the design of the Next Linear Collider Test Accelerator (NLCTA), a high-gradient, 1-GeV, Xband linac at SLAC. INTRODUCTIONThe Next Linear Collider Test Accelerator (NLCTA) is a high-gradient, X-band linac at SLAC designed to validate 2.6-cm microwave linear accelerator technology for a future high-energy linear collider (the Next Linear Collider).' This report describes the ionizing radiation protection and safety issues in the design of the NLCTA, including power limits, shielding, and safety systems.* The NLCTA beam line ( Fig. 1) consists of an injector, chicane, linac, and spectrometer. The injector contains a 3-A, 1 50-kV, pulsed thermionic-cathode gun and two 0.9-m-long X-band accelerator ~ections.~ The sections are energized by a single 50-MW klystron, and boost the beam energy by up to 90 MeV (50 MV/m). The gun pulse has 0.125-ps duration. The repetition rate is