Bright $\gamma$ rays source and copious nonlinear Breit-Wheeler pairs in the collision of high density particle beams

F. Del Gaudio, T. Grismayer, R. A. Fonseca +2

The collision of ultrashort high-density $e^{-}$ or $e^{-}$ and $e^{+}$ beams at 10s of GeV, to be available at the FACET II and in laser wakefield accelerator experiments, can produce h…