Photon jets from laser-plasma interactions

Advances in high-intensity laser technology have suggested new ways to generate high-flux, short-duration beams of high-energy particles. Numerical simulations have shown that laser intensities >10²¹ W/cm² incident on opaque plasma targets yield high-energy photon (E_γ>1 MeV) fluxes of 10⁹ up to 10¹² per sterradian. When the laser intensity and plasma density are matched such that the laser creates a low-density channel through the target, the photon flux is concentrated into two jet-like regions aligned with the polarization plane. We quantify the collimation of the photon jets by introducing a jet energy observable, which can be straightforwardly measured and offers a quality measure of the photon beam. We use the observable to demonstrate that the jet phenomenon survives and can be enhanced under non-ideal laser and plasma initial conditions.

[1] Jet Observable for Photons from High-Intensity Laser-Plasma Interactions, arXiv:1808.07067 [physics.plasm-ph]