Electron-Ion Temperature Ratio in Transrelativistic Unmagnetized Shock Waves

Abstract

Weakly magnetized shock waves are paramount to a large diversity of environments, including supernova remnants, blazars, and binary-neutron-star mergers. Understanding the distribution of energy between electrons and ions within these astrophysical shock waves spanning a wide spectrum of velocities is a long-standing challenge. In this study, we present a unified model for the downstream electron temperature within unmagnetized shock waves. Encompassing velocities from Newtonian to relativistic, we probe regimes representative of the gradual deceleration of the forward shock in the late gamma-ray burst afterglow phase, such as GRB 170817A. In our model, heating results from an ambipolar electric field generated by the difference in inertia between electrons and ions, coupled with rapid electron scattering in the decelerating turbulence. Our findings demonstrate that the electron temperature consistently represents $10\%$ of the incoming ion kinetic energy in the shock front frame over the full range of shock velocities.

Proceedings of HEPRO VIII (Paris 2023)

References in corpus (21)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Generation of Magnetic Fields in the Relativistic Shock of Gamma-Ray-Burst Sources
• The Maximum Energy of Accelerated Particles in Relativistic Collisionless Shocks
• On the structure of relativistic collisionless shocks in electron-ion plasmas
• Simulations of relativistic collisionless shocks: shock structure and particle acceleration
• Non-relativistic Collisionless Shocks in Unmagnetized Electron-Ion Plasmas
• Electron-Ion Temperature Equilibration in Collisionless Shocks: the Supernova Remnant-Solar Wind Connection
• Observational Evidence for Stochastic Shock Drift Acceleration of Electrons at the Earth's Bow Shock
• Physics of Weibel-mediated relativistic collisionless shocks
• Suppressing the Numerical Cherenkov Instability in FDTD PIC Codes
• 3D modeling of collisionless shocks
• Electron-Ion Temperature Ratio in Astrophysical Shocks
• Thermal Electrons in Mildly-relativistic Synchrotron Blast-waves
• Physics of relativistic collisionless shocks: The scattering center frame
• Long-term Evolution of Relativistic Unmagnetized Collisionless Shocks
• Physics of relativistic collisionless shocks: II Dynamics of the background plasma
• Origin of intense electron heating in relativistic blast waves
• Electron heating in high Mach number collisionless shocks
• The role of plasma instabilities in relativistic radiation mediated shocks: stability analysis and particle-in-cell simulations
• Probing particle acceleration at trans-relativistic shocks with off-axis gamma-ray burst afterglows
• The Peak Frequency and Luminosity of Synchrotron Emitting Shocks: from Non-Relativistic to Ultra-Relativistic Explosions