Radiation-dominated injection of positrons generated by the nonlinear Breit-Wheeler process into a plasma channel, now on POP
The work Radiation-dominated injection of positrons generated by the nonlinear Breit-Wheeler process into a plasma channel by former epp intern Dominika M and epp members Bertrand M and Marija V is now out in the journal Physics of Plasmas. In this paper, electron-positron pair generation by an orthogonal collision of a multi-PW laser pulse and a GeV electron beam by the nonlinear Breit-Wheeler process was studied. Conditions required for positron deflection in the direction of the laser pulse propagation were analyzed, which favors injection into plasmas. Using the OSIRIS particle-in-cell framework, it was demonstrated that the radiation reaction triggered by ultra-high laser intensity plays a crucial role in the positron injection. It provides a suppression of the initial transverse momentum gained by the positrons from the Breit-Wheeler process. A fraction of the positrons that are deflected are available for direct laser acceleration in a plasma channel, providing a one-stage plasma-based positron accelerator.