2017/09/11 by Ashutosh Sharma, Sharma, Ashutosh · 2 citations
Physics and Astronomy · #Laser-Plasma Interactions and Diagnostics #Gamma-ray bursts and supernovae #Astro and Planetary Science
paper · pdf · doi:10.48550/arxiv.1709.03287
We demonstrate in this research the quasi-monoenergetic electron and proton\nacceleration through three dimensional particle-in-cell simulations of short\npetawatt circular polarized laser pulse interactions with near critical density\nhydrogen target. We numerically show that under controlled choice of laser and\ntarget parameters, the high energy electrons and protons can be illustrated in\nexperiment at advanced high power laser facilities eg ELI - ALPS. We detailed\nthe microphysics involved in the acceleration mechanism, which required\ninvestigating the role of plasma density gradients, plasma density, and target\nthickness. The role of selfgenerated plasma electric and magnetic fields is\ndepicted on proton energy and density distribution. We numerically investigate\nhere the laser driven proton acceleration where energetic protons with energies\nmore than 200 MeV and charge in excess of 10 nC and conversion efficiency more\nthan 6 percent (which implies 2.4 J proton beam out of the 40 J incident laser\nenergy). Additionally and interestingly, we show from simulation study first\ntime the quasi-monoenergetic ring shaped electron beam driven by circularly\npolarised laser which may prove useful for plasma based-based X-ray source and\ncollimation of positron beam.\n