Electron Weibel instability in relativistic counterstreaming plasmas with flow-aligned external magnetic fields
Year: 2017
Authors: Grassi A., Grech. M., Amiranoff F., Pegoraro F., Macchi A., Riconda C.
Autors Affiliation: Univ Paris Saclay, UPMC Univ Paris 06, Sorbonne Univ, CNRS,Ecole Polytech,CEA,LULI, F-75252 Paris 05, France; Univ Pisa, Dipartimento Fis Enrico Fermi, Largo Bruno Pontecorvo 3, I-56127 Pisa, Italy; CNR, INO, I-56127 Pisa, Italy; Sorbonne Univ, UPMC Univ Paris 06, Univ Paris Saclay, LULI,CNRS,Ecole Polytech,CEA, F-91128 Palaiseau, France.
Abstract: The Weibel instability driven by two symmetric counterstreaming relativistic electron plasmas, also referred to as current-filamentation instability, is studied in a constant and uniform external magnetic field aligned with the plasma flows. Both the linear and nonlinear stages of the instability are investigated using analytical modeling and particle-in-cell simulations. While previous studies have already described the stabilizing effect of the magnetic field, we show here that the saturation stage is only weakly affected. The different mechanisms responsible for the saturation are discussed in detail in the relativistic cold fluid framework considering a single unstable mode. The application of an external field leads to a slight increase of the saturation level for large wavelengths, while it does not affect the small wavelengths. Multimode and temperature effects are then investigated. While at high temperature the saturation level is independent of the external magnetic field, at low but finite temperature the competition between different modes in the presence of an external magnetic field leads to a saturation level lower with respect to the unmagnetized case.
Journal/Review: PHYSICAL REVIEW E
Volume: 95 (2) Pages from: 023203-1 to: 023203-14
More Information: The authors thank Laurent Gremillet for fruitful discussions and the SMILEI development team for technical support. A.G. and C.R. acknowledge financial support from Grant No. ANR-11-IDEX-0004-02 Plas@Par. A.G. acknowledges support from the Universite Franco-Italienne through the Vinci program. This work was performed using High Performance Computing resources from GENCI-TGCC (Grant No. 2016-x2016057678).KeyWords: Weibel instability; Filamentation instability; DOI: 10.1103/PhysRevE.95.023203Citations: 34data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-12-01References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here