Compact and spatially coherent X-ray source based on cryogenic ERL. Basic design of the X-ray radiator

The development of spatially coherent X-ray generator based on the compact energy recovery linac (ERL) has been studied in collaboration with Nihon University, High Energy Accelerator Research Organization (KEK) and Toyama. In this novel source, parametric X-ray radiation (PXR), which is a radiation phenomenon caused by the interaction between a charged particle and a crystal medium, is used for X-ray production. Thus, a thin crystal plate such as silicon or diamond irradiated with the electron beam from the ERL acts as an X-ray radiator. Since the acceptance of the deceleration tube restricts the emittance growth of the electron beam at the radiator, we define the maximum thickness of the radiator crystal as 0.2 mm. Under this condition, the properties of the available PXR beam were investigated using Monte Carlo simulations. The results show possibility of X-ray photon rate higher than 10⁹ /s when the electron beam current is 30 μA. (author)