Analysis of the Effect of Pulse Width on Nonlinear Thomson Scattering from an Applied Magnetic Field

Abstract

The effects of magnetic fields on electron dynamics, spatially radiated power, and radiation spectra in tightly focused circularly polarized laser pulses are studied in detail. The laser wavelength λ0=1 μm. As the pulse width increases from λ0 to 6λ0, the electron dynamics, spatially radiated power, and spectral properties stabilize, and the benefit that can be enhanced by increasing the pulse width decreases continuously, i.e., saturation is reached. However, although the benefits are better at pulse widths equal to 6λ0, to obtain high-energy, highly collimated X-rays, tightly focused circularly polarized laser pulses with larger pulse widths is better.