High Power Gamma-Ray Flash Generation in Ultra Intense Laser-Plasma   Interaction
  When high-intensity laser interaction with matter enters the regime of dominated radiation reaction, the radiation losses open the way for producing short pulse high power gamma ray flashes. The gamma-ray pulse duration and divergence are determined by the laser pulse amplitude and by the plasma target density scale length. On the basis of theoretical analysis and particle-in-cell simulations with the radiation friction force incorporated, optimal conditions for generating a gamma-ray flash with a tailored overcritical density target are found. 
Tatsufumi Nakamura, James K. Koga, Timur Zh. Esirkepov, Masaki Kando,   Georg Korn, and Sergei V. Bulanov
physics.plasm-ph