Simulation of a collisionless planar electrostatic shock in a proton–electron plasma with a strong initial thermal pressure change
- 18 January 2010
- journal article
- research article
- Published by IOP Publishing in Plasma Physics and Controlled Fusion
Abstract
The localized deposition of the energy of a laser pulse, as it ablates a solid target, introduces high thermal pressure gradients in the plasma. The thermal expansion of this laser-heated plasma into the ambient medium (ionized residual gas) triggers the formation of non-linear structures in the collisionless plasma. Here an electron-proton plasma is modelled with a particle-in-cell simulation to reproduce aspects of this plasma expansion. A jump is introduced in the thermal pressure of the plasma, across which the otherwise spatially uniform temperature and density change by a factor of 100. The electrons from the hot plasma expand into the cold one and the charge imbalance drags a beam of cold electrons into the hot plasma. This double layer reduces the electron temperature gradient. The presence of the low-pressure plasma modifies the proton dynamics compared with the plasma expansion into a vacuum. The jump in the thermal pressure develops into a primary shock. The fast protons, which move from the hot into the cold plasma in the form of a beam, give rise to the formation of phase space holes in the electron and proton distributions. The proton phase space holes develop into a secondary shock that thermalizes the beam.This publication has 32 references indexed in Scilit:
- Rarefaction Acceleration and Kinetic Effects in Thin-Foil Expansion into a VacuumPhysical Review Letters, 2009
- Observation of Collisionless Shocks in Laser-Plasma ExperimentsPhysical Review Letters, 2008
- Electron kinetic effects in plasma expansion and ion accelerationPhysical Review E, 2008
- Explosion implosion duality and the laboratory simulation of astrophysical systemsPhysics of Plasmas, 2000
- Rescaling methods and plasma expansions into vacuumPhysics of Fluids B: Plasma Physics, 1993
- The virtual particle electromagnetic particle-mesh methodComputer Physics Communications, 1991
- Double layer formation caused by contact between different temperature plasmasPhysics of Fluids, 1985
- Particle simulation of plasmasReviews of Modern Physics, 1983
- Filamentary Instability of a Relativistic Electron BeamPhysical Review Letters, 1975
- Theory of Laminar Collisionless ShocksPhysical Review Letters, 1971