Synchronization of femtosecond UV-IR laser with electron beam for pulse radiolysis studies

A picosecond stroboscopic pulse radiolysis system which consists of a femtosecond laser and a picosecond L-band linear accelerator (linac) is demonstrated. A newly installed femtosecond laser system operated at 960 Hz can cover a wide region of wavelength ranging from <300 nm to 10 μm, although the upper limit is 1.7 μm to date because of the sensitivity of photodetectors. In order to achieve a high accuracy of synchronization between the laser and the linac, a new timing and synchronization circuit was developed. A double pulse detection method was applied for the new system, resulting in doubling of the improvement in signal-to-noise ratio. The time resolution and time jitter were estimated from the rise time of hydrated electrons at 600 nm, and the transient absorption kinetics of electrons in n-dodecane was measured at 1300 nm.