Progress update on compressed ultrashort pulse injector demonstrator

Stable high gradient operation of a photoinjector is important for generating high brightness electron beams. The Argonne Wakefield Accelerator (AWA) facility recently commissioned an X-band photoinjector at 400 MV/m cathode field without significant breakdown rates using nanosecond RF pulses generated from a wakefield accelerator. We propose to develop an X-band photoinjector at 500 MV/m cathode field fed by ultrashort RF pulses generated by RF pulse compression technology developed at SLAC National Accelerator Laboratory, named as Compressed Ultrashort Pulse Injector Demonstrator (CUPID). The klystron based pulse compression is more stable and allows higher repetition rate. Here we provides the progress update of CUPID project, in particular on the mechanical design of the electron gun, solenoid's requirement and design constraints.