Backward Compton scattering of picosecond CO/sub 2/ laser pulses using relativistic electron beam for the bright X-ray generation

Laser-Compton scattering can generate X-rays or γ-rays with high brightness by applying high-peak-power laser pulses to relativistic electron bunches. We have proposed laser-Compton scattering to generate polarized γ-rays which can induce pair-creation to produce polarized positrons for JLC (Japan Linear Collider) project. As a photon source of the Compton scattering, a picosecond CO/sub 2/ laser system is going to be applied for our experiment because of the higher scattering cross section than near-infrared solid-state lasers, laser power scalability, the laser efficiency and the possibility of high-repetition rated operation. In our experiment, CO/sub 2/ laser pulses with a pulsewidth of about 180 ps are generated by the optical semiconductor slicing method. The sliced CO/sub 2/ pulses are amplified up to 6 GW by a regenerative amplifier with a high-pressure TE CO/sub 2/ laser system.