The transport of cosmic rays in self-excited magnetic turbulence
The process of diffusive shock acceleration relies on the efficacy with which hydromagnetic waves can scatter charged particles in the precursor of a shock. The growth of self-generated waves is driven by both resonant and non-resonant processes. We perform high-resolution magnetohydrodynamic simula...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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2008
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| _version_ | 1826294428764995584 |
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| author | Reville, B O'Sullivan, S Duffy, P Kirk, J |
| author_facet | Reville, B O'Sullivan, S Duffy, P Kirk, J |
| author_sort | Reville, B |
| collection | OXFORD |
| description | The process of diffusive shock acceleration relies on the efficacy with which hydromagnetic waves can scatter charged particles in the precursor of a shock. The growth of self-generated waves is driven by both resonant and non-resonant processes. We perform high-resolution magnetohydrodynamic simulations of the non-resonant cosmic ray driven instability, in which the unstable waves are excited beyond the linear regime. In a snapshot of the resultant field, particle transport simulations are carried out. The use of a static snapshot of the field is reasonable given that the Larmor period for particles is typically very short relative to the instability growth time. The diffusion rate is found to be close to, or below, the Bohm limit for a range of energies. This provides the first explicit demonstration that self-excited turbulence reduces the diffusion coefficient and has important implications for cosmic-ray transport and acceleration in supernova remnants. © 2008 RAS. |
| first_indexed | 2024-03-07T03:45:29Z |
| format | Journal article |
| id | oxford-uuid:bf5259ff-81c1-4d12-a83b-55c0238c86e3 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:45:29Z |
| publishDate | 2008 |
| record_format | dspace |
| spelling | oxford-uuid:bf5259ff-81c1-4d12-a83b-55c0238c86e32022-03-27T05:46:34ZThe transport of cosmic rays in self-excited magnetic turbulenceJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:bf5259ff-81c1-4d12-a83b-55c0238c86e3EnglishSymplectic Elements at Oxford2008Reville, BO'Sullivan, SDuffy, PKirk, JThe process of diffusive shock acceleration relies on the efficacy with which hydromagnetic waves can scatter charged particles in the precursor of a shock. The growth of self-generated waves is driven by both resonant and non-resonant processes. We perform high-resolution magnetohydrodynamic simulations of the non-resonant cosmic ray driven instability, in which the unstable waves are excited beyond the linear regime. In a snapshot of the resultant field, particle transport simulations are carried out. The use of a static snapshot of the field is reasonable given that the Larmor period for particles is typically very short relative to the instability growth time. The diffusion rate is found to be close to, or below, the Bohm limit for a range of energies. This provides the first explicit demonstration that self-excited turbulence reduces the diffusion coefficient and has important implications for cosmic-ray transport and acceleration in supernova remnants. © 2008 RAS. |
| spellingShingle | Reville, B O'Sullivan, S Duffy, P Kirk, J The transport of cosmic rays in self-excited magnetic turbulence |
| title | The transport of cosmic rays in self-excited magnetic turbulence |
| title_full | The transport of cosmic rays in self-excited magnetic turbulence |
| title_fullStr | The transport of cosmic rays in self-excited magnetic turbulence |
| title_full_unstemmed | The transport of cosmic rays in self-excited magnetic turbulence |
| title_short | The transport of cosmic rays in self-excited magnetic turbulence |
| title_sort | transport of cosmic rays in self excited magnetic turbulence |
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