Generation of ultrashort electron pulse for laser synchronized picosecond pulse radiolysis system

A pulse radiolysis system by using a femtosecond laser synchronized with electron linac was developed at Osaka University. This system has a potential to detect ultrafast phenomena in the femtosecond region. The pulse width of analyzing light is 100 fs. However, the present pulse width of the electron beam (irradiation source) is 20 ps. The pulse width of electron beams and the time jitter of the system mainly decide the time resolution of the whole system. We attempted to generate a shorter pulse by installing a magnetic pulse compressor to the L-band linac of Osaka University. The pulse width of electron beams was measured by a picosecond streak camera with a time resolution of 2 ps. 27 MeV electron pulses with the pulse width of 30 ps have been compressed to 2.4 ps, which is equal to the time resolution of the streak camera, by the magnetic pulse compression system. (author)