OBSERVATION OF INTENSE TERAHERTZ SYNCHROTRON RADIATION PRODUCED BY LASER BUNCH SLICING AT UVSOR-II

A laser bunch slicing experiment has started at the UVSOR-II electron storage ring. An ultra-short pulse laser system was introduced, which can be synchronized with the RF acceleration of the ring. A laser transport line was constructed by utilizing existing light ports for free electron laser. An undulator which is also used for the free electron laser can be tuned to the laser wavelength and is used for modulator. Intense terahertz pulses synchronized with the laser injection were successfully observed at an existing infrared beam line located downstream of the undulator section. The intensity of the terahertz pulses was proportional to the square of the peak intensity of the electron beam. This clearly indicates that the terahertz pulses were coherent synchrotron radiation originating from longitudinal density structure of the electron bunch produced by laser bunch slicing.