All-optical generation of petawatt gamma radiation via inverse Compton scattering from laser interaction with tube target.

A scheme for generating gamma photons from laser interaction with a hollow-tube target filled with near-critical-density plasma is investigated using quantum electrodynamics particle-in-cell simulation. The solid-density tube wall stabilizes the laser propagation in the tube, guides the laser-accelerated relativistic electrons, and its endplate reflects the laser light. As the electrons collide head-on with the reflected laser, a large number of MeV gamma photons are generated through inverse Compton scattering. It is found that bright gamma radiation with power up to 1.4 PW and 37% laser-to-gamma ray energy conversion efficiency can be obtained with 5 × 1022 W cm–2 laser pulse. [ABSTRACT FROM AUTHOR]