Shocks and phase space vortices driven by a density jump between two clouds of electrons and protons

0525017 - FZÚ 2021 RIV GB eng J - Journal Article
Moreno-Gelos, Quentin - Dieckmann, M.E. - Folini, D. - Walder, R. - Ribeyre, X. - Tikhonchuk, Vladimir - d'Humieres, E.
Shocks and phase space vortices driven by a density jump between two clouds of electrons and protons.
Plasma Physics and Controlled Fusion. Roč. 62, č. 2 (2020), s. 1-12, č. článku 025022. ISSN 0741-3335. E-ISSN 1361-6587
R&D Projects: GA MŠMT EF16_013/0001793
Grant - others:OP VVV - ELITAS(XE) CZ.02.1.01/0.0/0.0/16_013/0001793
Institutional support: RVO:68378271
Keywords : instability * collisionless * phase space vortices * ion acoustic instabilities * electrostatic shock
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.458, year: 2020
Method of publishing: Limited access
https://doi.org/10.1088/1361-6587/ab5bfb

We study with 1D PIC simulations the expansion of a dense plasma into a dilute one for density ratios 2.5„α„20. Both are unmagnetized and consist of electrons and protons. Shocks form in all cases. We determine how α affects the speed of the shock, that of the trailing velocity plateau and the proton beam instabilities in its upstream region. The speed of the velocity plateau relative to the upstream plasma increases significantly with α. Faster shocks reflect more upstream protons and fewer protons make it downstream, which slows down the shock in the downstream frame. This slow-down reduces noticably the increase with α of the shock speed in the upstream frame. All simulations demonstrate that an ion acoustic instability develops between the shock-reflected proton beam and the ambient protons.

Permanent Link: http://hdl.handle.net/11104/0309223