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arXiv · 1510.04338

Numerical Modeling on Thermal Loading of Diamond Crystal in X-ray FEL Oscillator

Meiqi Song·Qingmin Zhang·Yuhang Guo·Kai Li·Haixiao Deng
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Abstract

Due to high reflectivity and high resolution of X-ray pulses, diamond is one of the most popular Bragg crystals serving as the reflecting mirror and mono$-$chromator in the next generation of free electrons lasers (FELs). The energy deposition of X-rays will result in thermal heating, and thus lattice expansion of the diamond crystal, which may degrade the performance of X-ray FELs. In this paper, the thermal loading effect of diamond crystal for X-ray FEL oscillators has been systematically studied by combined simulation with Geant4 and ANSYS, and its dependence on the environmental temperature, crystal size, X-ray pulse repetition rate and pulse energy are presented. Our results show that taking the thermal loading effects into account, X-ray FEL oscillators are still robust and promising with an optimized design.

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Meiqi Song, Qingmin Zhang, Yuhang Guo, Kai Li, Haixiao Deng. 2015-12-04. Numerical Modeling on Thermal Loading of Diamond Crystal in X-ray FEL Oscillator. https://doi.org/10.1088/1674-1137%2F40%2F4%2F048101

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