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SUPERNOVA BLASTWAVES AND PRE-SUPERNOVA WINDS: THEIR COSMIC RAY CONTRIBUTION

Peter L. Biermann
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Abstract

Supernova explosions into predecessor stellar winds can lead to particle acceleration, which we suggest can explain most of the observed cosmic rays of the nuclei of Helium and heavier elements, from GeV in particle energies up to near $3 \, 10^9$ GeV, as well as electrons above about 30 GeV. We go through the following steps: 1) Using a postulated underlying principle that leads to transport coefficients in a turbulent plasma, we derive the properties of energetic particles accelerated in spherical shocks. 2) We suggest that a dynamo working in the inner convection zone of an upper main sequence star can lead to high magnetic field strengths. 3) Such magnetic fields may put additional momentum into stellar winds from the pressure gradient of the toroidal field. 4) We derive a lower limit for the magnetic field strengths. 5) There appears to be a critical Alfvénic Machnumber for electron injection. With this concept we propose an explanation for the observed proton/electron ratio in galactic cosmic rays at GeV energies. 6) We check the model prediction quantitatively on cosmic ray spectrum and chemical composition against airshower data and further cosmic ray data. 7) Finally, we summarize various important caveats, and outline important next steps as well as checks.

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Peter L. Biermann. 1995-01-10. SUPERNOVA BLASTWAVES AND PRE-SUPERNOVA WINDS: THEIR COSMIC RAY CONTRIBUTION. https://arxiv.org/abs/astro-ph/9501030

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