Recent Progress in the Theory of Electron Injection in Collisionless Shocks

Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 33)


The injection problem in diffusive shock acceleration theory is discussed with particular focus on electrons. The following issues are addressed: Why it has been considered to be so difficult, what is the required condition, and how it can be resolved. It is argued that there exists a critical Mach number above which the electron injection is achieved. Above the threshold, back-streaming electrons reflected back upstream by the shock front can self-generate high-frequency whistler waves, which can scatter themselves as required for subsequent acceleration. The theoretical estimate is found to be well consistent with in-situ measurements, indicating this could provide a possible solution to the long standing problem in the diffusive shock acceleration theory.


Shock Front Electron Injection Whistler Wave Loss Cone Collisionless Shock 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



T. A. is supported by the Global COE program of Nagoya University (QFPU) and KAKENHI 22740118 from JSPS and MEXT of Japan. This manuscript was written while one of the authors (T. A.) was visiting Max-Planck-Institut für Kernphysik at Heidelberg, Germany.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of PhysicsNagoya UniversityNagoyaJapan
  2. 2.Max-Planck-Institut für KernphysikHeidelbergGermany
  3. 3.Department of Earth and Planetary ScienceUniversity of TokyoTokyoJapan

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