Evolution of angular-resolved rate of Thomson scattering in intense laser fields

By employing a full quantum theory of electron–photon scattering in intense laser fields, we calculate the angular-resolved radiation rate of the fundamental wave in Thomson scattering. We investigate the dependence of radiation rate on Euler angles and elucidate the underlying physical mechanism. The figure-8 profile of the radiation rate within the polarization plane is validated, while its evolution with respect to laser intensity and electron momentum is illustrated. Our findings reveal that in lower-intensity laser fields and for slow electron motion, the angular-resolved radiation rate exhibits distinct dipole emission characteristics. However, significant changes are observed at high laser intensities and/or large electron momenta, leading to pronounced alterations in the angular-resolved radiation rate. Remarkably similar variation patterns can be achieved by proportionally adjusting both laser intensity and electron momentum.