Optimizing the energies conversion in laser-electron beam collision

The energy conversion in laser-electron beam collision is typically small. However, with a properly chosen parameter of the laser and electron beam, the energy conversion can be optimized. In this paper, the laser and electron parameters are selected such that the ponderomotive force is compensated by the radiation reaction force in the head-on collision configuration. Then, the relativistic electron beam can quiver in the laser pulse for a longer time to increase the energy conversion. To access the laser energy evolution, simulations of laser-electron beam collision by the Particle-in-Cell method are performed. The optimum of laser field energy depletion is observed at γ0 = a0 ∼ 400 and limited beyond this point due to the impenetrability threshold. The total energy conversion into radiation emission is optimum at γ0 = a0 ∼ 250. We estimated that the conversion efficiency can be up to 11% for an electron bunch with charge of the order of 100 nC. The efficient gamma-ray sources are of great interest for applications in photonuclear experiments.