Generation of attosecond coherent X-ray radiation through modulation compression.

In this paper, we propose a scheme to generate tunable attosecond coherent X-ray radiation for future light source applications. This scheme uses a short-pulse seeding laser, two bunch compressors, and a laser chirper to generate a prebunched, kilo-Ampere current electron beam from an initial 10-Ampere low-current electron beam. Such an electron beam sent into a short undulator generates attosecond coherent soft X-ray radiation. The final X-ray radiation wavelength can be tuned by adjusting the compression factor. It also allows one to control the final radiation pulse length by controlling the seeding laser pulse length or the compression factor. As an illustration, we present an example to generate 1 GW, 200 attosecond, 1 nm coherent X-ray radiation from a 28 A current, 200 nm laser modulated beam. [ABSTRACT FROM AUTHOR]