Effect and mechanism of initial phase on electron radiation under linearly polarized Gaussian laser pulse

In this paper, through numerical simulation, the effect of initial phase on nonlinear Thomson scattering in a Gaussian laser pulse under tight focusing is studied. It is found for the first time that the initial phase is out of synchronization with the maximum radiation angle. When the initial phase changes from 360° to 180°, the maximum radiation distribution appears multi peak phenomenon, and the degree of the initial phase angle is different from that when the initial phase changes from 0 to 180 degrees., it shows an antisymmetric variation law. Furthermore, we discuss the process and reason of this phenomenon, which provides a accurate observation time and theoretical basis for high energy electron radiation experiment.