Colloquium
Department of Physics, NCU
High brightness electron linear accelerator and light source R&D at NSRRC
Speaker
Prof. Wai-Keung Lau (劉偉強)
High Brightness Injector Group, Light Source Division
National Synchrotron Radiation Research Center (NSRRC)
Date 2019.04.16(Tue)
Time 14:00-16:00
Place S4-625
Abstract : Significant progress has been made over the past decades on development of high brightness electron linac technology for various novel applications such as x-ray free electron lasers (FELs), -ray sources based on inverse Compton scattering, and ultrafast electron microscopy etc.. Laser-driven photo-cathode rf gun has proven to be one of the most successful candidates that deliver high brightness relativistic electron beam for those advanced applications. An S-band photo-cathode rf gun system had been developed in-house at NSRRC and being operated regularly since 2013. With this electron gun, a linac system has been installed recently and a high brightness sub-picosecond electron beam has been produced successfully by use of the “velocity bunching” mechanism in the rf linac of the injector. Intense single-cycle coherent THz radiation has been generated by hitting such beam on metallic foils and a multi-cycle coherent THz radiation has been obtained by passing the beam through a 1.8-m planar undulator of 100-mm period length. Based on the experiences accumulated in the past several years, and with mostly the existing hardware in-house, we are moving forward to plan a FEL test facility that provides tunable coherent radiation in THz as well as the vacuum ultraviolet (VUV) regions. The feasibility to turn this test device into a facility that serves local user community is also under consideration.