Electron heating in high Mach number collisionless shocks

Abstract

The energy partition in high Mach number collisionless shock waves is central to a wide range of high-energy astrophysical environments. We present a new theoretical model for electron heating that accounts for the energy exchange between electrons and ions at the shock. The fundamental mechanism relies on the difference in inertia between electrons and ions, resulting in differential scattering of the particles off a decelerating magnetically-dominated microturbulence across the shock transition. We show that the self-consistent interplay between the resulting ambipolar-type electric field and diffusive transport of electrons leads to efficient heating in the magnetic field produced by the Weibel instability in the high-Mach number regime and is consistent with fully kinetic simulations.

10 pages, 6 figures, 1 table; Accepted for publication in Physical Review Letters

References in corpus (20)

• Electron Shock Surfing Acceleration in Multidimensions: Two-dimensional Particle-In-Cell Simulation of Collisionless Perpendicular Shock
• Electron Surfing and Drift Accelerations in a Weibel-dominated High-Mach-number Shock
• Nonrelativistic collisionless shocks in weakly magnetized electron--ion plasmas: two-dimensional particle-in-cell simulation of perpendicular shock
• Physics of Weibel-mediated relativistic collisionless shocks
• Generalized Fermi acceleration
• Collisionless shock heating of heavy ions in SN 1987A
• Electron Preacceleration in Weak Quasi-perpendicular Shocks in High-beta Intracluster Medium
• Magnetic field amplification by the Weibel instability at planetary and astrophysical high-Mach-number shocks
• Particle Transport in intense small scale magnetic turbulence with a mean field
• Electron-Ion Temperature Ratio in Astrophysical Shocks
• Kinetic simulations of nonrelativistic perpendicular shocks of young supernova remnants. III. Magnetic reconnection
• Multi-scale dynamics of magnetic flux tubes and inverse magnetic energy transfer
• Electron Heating in Low Mach Number Perpendicular shocks. I. Heating Mechanism
• Magnetic field amplification by a nonlinear electron streaming instability
• Physics of relativistic collisionless shocks: The scattering center frame
• Electron Heating in Perpendicular Low-Beta Shocks
• Origin of intense electron heating in relativistic blast waves
• The role of plasma instabilities in relativistic radiation mediated shocks: stability analysis and particle-in-cell simulations
• Pre-acceleration in the Electron Foreshock II: Oblique Whistler Waves
• Efficient generation of turbulent collisionless shocks in laser-ablated counter-streaming plasmas

Cited by in corpus (4)

• Magnetic Field Amplification and Particle Acceleration in Weakly Magnetized Trans-relativistic Electron-ion Shocks
• Energy partition in collisionless counterstreaming plasmas
• Electron-Ion Temperature Ratio in Transrelativistic Unmagnetized Shock Waves
• Ion Weibel Instability in the hybrid framework: the optimal resolution