Nonlinear Thomson scattering for off-axis interaction geometries

We examine the generation of X-rays via nonlinear Thomson scattering of intense lasers from relativistic electron beams, with particular attention to off-axis scattering geometries. We present analytic expressions for the intensity distribution of the scattered radiation, valid in the nonlinear regime (arbitrary laser intensity) and including the generation of harmonics. Spectra are plotted numerically for the specific cases of head-on and transverse scattering. The dependence of X-ray pulse duration and photon flux on interaction geometry are also examined.