The generation of collimated γ-ray pulse from the interaction between 10 PW laser and a narrow tube target

A scheme to radiate a highly collimated gamma-ray pulse is proposed through the interaction between an ultra-intense laser pulse and a narrow tube target. The gamma-ray pulse, with high conversion efficiency, can be generated as a result of electron acceleration in a longitudinal electric field. In a Particle-inCell simulation with a 10-PW laser, 18% of the laser energy is transferred into the forward gamma-ray in a divergence angle less than 3 degrees. It is also found that such a highly collimated gamma-ray pulse can be produced with a large range of tube diameters and laser intensities. This scheme could be realized in experiment with the coming 10-PW class lasers in the near future. Published by AIP Publishing.