Simulation of wire scanner for high repetition free electron laser facilities

Abstract

The high-gain Free Electron Lasers (FEL) have promised scientists for new scientific discoveries in many frontier research areas. For that purpose, this kind of facilities have been installed or will be installed worldwide. As to FELs, high repetition is the future development trend. Herein, wire scanner provides a measurement of beam profile which realizes real-time and non-intercepting for the FELs. The simulation of key parameters of wire scanner for the FELs is discussed in this paper. Since wire scanner for FELs mainly use tungsten wires, then empirical formula for optimum installation position of Beam Loss Monitor (BLM) and empirical formula for the maximum temperature of tungsten wires are given based on theoretical analysis and numerical simulation. These formulas can provide a reference for high repetition and high-gain FELs that will be installed with wire scanners in the future. In recent years, the Shanghai HIgh repetition rate XFEL aNd Extreme light facility (SHINE), a quasi-continuous wave hard X-ray free electron laser facility, is under construction in China. Upon its completion, the linear accelerator will accelerate electrons with bunch charge of 10–300 pC to 8 GeV, at a maximum repetition frequency of 1 MHz. We calculate key parameters of the wire scanner for SHINE with these empirical formulas.