WEOAA1
LBNL, Berkeley, California, USA
SLAC, Menlo Park, California, USA
JLAB, Newport News, Virginia, USA
Fermilab, Batavia, USA
We present an overview of design studies and R&D toward NGLS a Next Generation Light Source initiative at LBNL. The design concept is based on a multi-beamline soft x-ray FEL array powered by a CW superconducting linear accelerator, and operating with a high bunch repetition rate of approximately 1 MHz. The linac design uses TESLA and ILC technology, supplied by an injector based on a CW normal-conducting VHF photocathode electron gun. Electron bunches from the linac are distributed by RF deflecting cavities to the array of independently configurable FEL beamlines with nominal bunch rates of ~100 kHz in each FEL, with uniform pulse spacing, and some FELs capable of operating at the full linac bunch rate. Individual FELs may be configured for different modes of operation, including self-seeded and external-laser-seeded, and each may produce high peak and average brightness x-rays with a flexible pulse format.
LBNL, Berkeley, California, USA
USTC/NSRL, Hefei, Anhui, People's Republic of China
The commissioning at the Lawrence Berkeley National Laboratory (LBNL) of a high-brightness high-repetition rate (MHz-class) photo-gun, based on a normal conducting 186 MHz (VHF-band) RF cavity operating in CW mode, is now completed. The gun has been designed to satisfy the requirements for operating high-repetition rate 4th generation light sources. Test of high quantum efficiency photocathodes with bunches of hundreds pC at MHz repetition rate are now underway. They include, Cs2Te cathodes developed in collaboration with INFN-LASA and multialkali antimonides (CsK2Sb), prepared by a collaborating group at LBNL. The present experimental results and the plan for future activities are presented.