Laser System with a Photocathode RF Gun at the Pohang Accelerator Laboratory

At the Pohang Accelerator Laboratory, a photocathode RF gun has been studied for a photoinjector of the 4th generation light source. This photocathode RF gun provides electron bunches with an energy of 5 MeV, a charge of 1 nC, and a bunch length of 10 ps. For this purpose, a Ti:Sapphire laser system that can deliver laser pulses of 2 mJ in energy and 110 fs in pulse width at a 800-nm wavelength was installed. The laser pulse passes through a third harmonic generator and pulse stretcher to generate a 266-nm laser pulse with a controllable pulse width (I ps similar to 15 ps). In this article, we introduce our laser system and report on recent progress in electron beam generation.