Spectral Shape Of Quasi-Monochromatic Radiation From Electron Colliding With Tightly Focused Laser Pulses

We theoretically investigate spectra of emitted light in nonlinear Thomson backscattering, which is generated during the head-on collision of the electron and the tightly focused circularly polarized laser pulse. With numerical analysis, a novel approach of generating quasi-monochromatic x-rays is obtained. By properly setting the electron-laser interaction point, limiting the laser intensity, and increasing pulse duration, the emission spectral bandwidth would be effectively narrowed without reducing the radiant energy of the electrons. In the end, the optimal situations for obtaining the quasi-monochromatic x-ray source are presented.