Emerging Terawatt Picosecond CO2 Laser Technology and Possible Applications in Accelerator Physics

Book excerpt: The first terawatt picosecond (TWps) CO2 laser is under construction at the BNL Accelerator Test Facility (ATF). TWps-CO2 lasers, having the order of magnitude longer wavelength than the well-known table-top terawatt solid state lasers, offer new opportunities for the strong-field physics research. For processes based on electro quiver motion, such as laser wakefield acceleration (LWFA), the advantage of the new class of lasers is due to a gain of two orders of magnitude in the ponderomotive potential for the same peak power. The large average power capability of CO2 lasers is important for the generation of hard radiation through Compton back-scattering of the laser off energetic electron beams, as well as for other applications. Among them are: LWFA modules of a tentative electron-positron collider, [gamma]-[gamma] (or [gamma]-lepton) collider, a possible table-top source of high-intensity x-rays and gamma rays and the generation of polarized positron beams.