Photonuclear fission with quasimonoenergetic electron beams from laser wakefields

Abstract

Recent advancements in laser wakefield accelerators have resulted in the generation of low divergence, hundred MeV, quasimonoenergetic electron beams. The bremsstrahlung produced by these highly energetic electrons in heavy converters includes a large number of MeV γ rays that have been utilized to induce photofission in natural uranium. Analysis of the measured delayed γ emission demonstrates production of greater than 3×105 fission events per joule of laser energy, which is more than an order of magnitude greater than that previously achieved. Monte Carlo simulations model the generated bremsstrahlung spectrum and compare photofission yields as a function of target depth and incident electron energy.