Proposition of a femtosecond pulse radiolysis with terahertz probe pulses.

Abstract A new concept of pulse radiolysis based on a photoinjector, which can synchronously offer femtosecond (fs) pump electron beams and intense Terahertz (THz) probe pulses, is proposed and studied in this paper. The two electron beams are generated in the radio-frequency (rf) electron gun by illuminating the photocathode with two laser pulses, then compressed and accelerated in two linear accelerators respectively. By applying the brake-applied velocity bunching bunch compression method, a few hundreds of fs electron beams with nano-Coulomb (nC) bunch charge can be obtained. The front beam can generate THz pulse with MW peak power for THz probe, and the rear beam is used to pumping the radiation induced phenomena. This new concept pulse radiolysis scheme provides a promising way for high time resolution pump-probe experiments with a novel experimental methodology. Highlights • A femtosecond pulse radiolysis with high intensity Terahertz probe is proposed. • Providing a promising way for pump-probe experiments. • Electron beam has a femtosecond length with a nano-Coulomb charge. • THz radiation is broadband with a MW peak power. • This scheme is very compact and has a high time resolution. [ABSTRACT FROM AUTHOR]