Powerful Long-Pulse THz-Band Bragg FEL Based On Linear Induction Accelerator

Project of high-power long-pulse THz FEL is initiated in collaboration between BINP and IAP RAS based on the linac 5 - 20 MeV/2 kA/200 ns of the new generation. The aim of this project is to achieve a record power level of ~100 MW and pulse energy content up to 10 J in the THz band. An advanced Bragg resonator capable to provide stable narrowband generation in strongly oversized interaction space is one of the key components of this FEL. Proof-of-principle operation of FEL with the resonator of such type has been already demonstrated up to W-band and narrow band generation at multi-MW power level has been observed for the transverse oversize factor of ~5 wavelengths. The paper presents design parameters and results of simulations of novel THz-band FEL.