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arXiv · 1906.02508

Cosmic Ray Acceleration in Hydromagnetic Flux Tubes

Anthony Bell·James Matthews·Katherine Blundell·Anabella Araudo
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Abstract

We find that hydromagnetic flux tubes in back-flows in the lobes of radio galaxies offer a suitable environment for the acceleration of cosmic rays (CR) to ultra-high energies. We show that CR can reach the Hillas (1984) energy even if the magnetised turbulence in the flux tube is not sufficiently strong for Bohm diffusion to apply. First-order Fermi acceleration by successive weak shocks in a hydromagnetic flux tube is shown to be equivalent to second-order Fermi acceleration by strong turbulence.

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Anthony Bell, James Matthews, Katherine Blundell, Anabella Araudo. 2019-06-06. Cosmic Ray Acceleration in Hydromagnetic Flux Tubes. https://doi.org/10.1093/mnras/stz1604

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