Symmetric and asymmetric shocked gas jets for laser-plasma experiments

Abstract

Shocks in supersonic flows offer both a high-density and sharp density gradients that can be used, for instance,for gradient injection in laser-plasma accelerators. We report on a parametric study of oblique shocks created by inserting a straight axisymmetric section at the end of a supersonic "de Laval" nozzle. The impact of different parameters such as throat diameter and straight section length is studied through computational fluid dynamics (CFD) simulations. Experimental characterizations of a shocked nozzle are compared to CFD simulations and found to be in good agreement. We then introduce a newly designed asymmetric shocked gas jet, where the straight section is only present on one lateral side of the nozzle, thus providing a gas profile that can be used for density transition injection. In this case, full-3D fluid simulations and experimental measurements are compared and show excellent agreement.

References in corpus (5)

• All-optical Compton gamma-ray source
• Compression of CEP-stable multi-mJ laser pulses down to 4 fs in long hollow fibers
• Short Intense Laser Pulse Collapse in Near-Critical Plasma
• Demonstration of stable long-term operation of a kilohertz laser-plasma accelerator
• Concept of a laser-plasma based electron source for sub-10 fs electron diffraction