Emerging Terawatt Picosecond CO[sub 2] Laser Technology and Possible Applications in Accelerator Physics

Book excerpt: The first terawatt picosecond (TWps) CO[sub 2] laser is under construction at the BNL Accelerator Test Facility (ATF). TWps-CO[sub 2] 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 CO[sub 2] 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.