Probing of nonlinear evolution of laser wakefield by Raman scattering of laser light

Zhou, W.*; Mima, Kunioki*; Nakamura, Tatsufumi; Nagatomo, Hideo*

When a weak probe laser pulse is injected into a wakefield excited by a short high-intensity pump laser pulse, the probe pulse will be Raman scattered by the wakefield. It is possible to determine the density profile from the spectrum of this forward Raman scattered probe laser. In previous research, an analytical solution for the multiple sidebands of the forward Raman scattering of the probe laser pulse was presented. These multiple sidebands are connected with the steepening of density perturbation of the wakefield. More detailed information of the probe pulse in wakefield is studied with one-dimensional particle-in-cell simulations. The analytical solution and the results of simulation are consistent with each other and other experiments.