Electron Acceleration at Rippled Low-mach-number Shocks in High-beta Collisionless Cosmic Plasmas

  title={Electron Acceleration at Rippled Low-mach-number Shocks in High-beta Collisionless Cosmic Plasmas},
  author={Oleh Kobzar and Jacek Niemiec and Takanobu Amano and Masahiro Hoshino and Shuichi Matsukiyo and Yosuke Matsumoto and Martin Pohl},
  journal={The Astrophysical Journal},
Using large-scale fully kinetic two-dimensional particle-in-cell simulations, we investigate the effects of shock rippling on electron acceleration at low-Mach-number shocks propagating in high-β plasmas, in application to merger shocks in galaxy clusters. We find that the electron-acceleration rate increases considerably when the rippling modes appear. The main acceleration mechanism is stochastic shock-drift acceleration, in which electrons are confined at the shock by pitch-angle scattering… Expand
Re-acceleration of Cosmic Ray Electrons by Multiple ICM Shocks
  • Hyesung Kang
  • Physics
  • 2021
Radio relics could be generated by multiple shocks induced in the turbulent intracluster medium during galaxy mergers. Kang (2021) demonstrated that the re-acceleration of cosmic ray (CR) protons viaExpand


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Electron acceleration at quasi-perpendicular shocks in sub- and supercritical regimes: 2D and 3D simulations
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