Estimation of the Survivability of Boron Carbide and Steel Struck by the Direct FEL X-Ray Beam of LCLS

A framework for estimating the energy deposited in a material struck by a direct FEL x-ray beam is presented. This framework is applied to the case of boron carbide and stainless steel struck by the FEL beam of the Linac Coherent Light Source (LCLS), and the results are compared to the thermal damage thresholds of these materials. The ability of these materials to withstand the beam is dependent on the photon energy, the distance between the material and the undulator, and the degree of beam focusing.