Optimizing the electron temperature for applications including laser driven radiography*

The process by which high-intensity lasers accelerate electrons to high energies has been the subject to many experimental, computational, and theoretical studies over the past 3 decades. Many the proposed applications of laser-driven sources from solid targets, principally MeV radiography, depend heavily on optimizing the acceleration of the electrons and in particular the  optimizing the electron temperature. Previously, scaling relations of the electron temperature were solely dependent on the intensity and wavelength of the laser (Iλ²), but more recently models have been developed to incorporate the laser pulse duration and scale length of the pre-plasma.  Through a thorough literature review, we have gathered hundreds of published experimental and simulated measurements of the electron temperature and have attempted, using Bayesian inference and other techniques, developed additional scaling laws. We test and compare these new scaling laws with existing ones and propose laser and plasma parameters that can optimize the production of MeV x-rays.