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Full-Text Articles in Physical Sciences and Mathematics
Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama
Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama
STAR Program Research Presentations
Supernova remnants (SNRs) are considered to be the primary energy source of galactic-origin cosmic rays. Within this prediction exist two models, leptonic and hadronic, to explain the acceleration of charged particles up to a PeV in energy. Using data from the Fermi Gamma-ray Space Telescope (FGST) each model is expected to produce a distinct spectral energy distribution (SED) over a photon energy range of 100MeV to 100GeV. This analysis is focused on the methods for generating SEDs for the SNR Cassiopeia A and how they can be used to constrain the likelihood of either acceleration model.
A Cosmic Ray Current-Driven Instability In Partially Ionised Media, Brian Reville, John Kirk, Peter Duffy, Stephen O'Sullivan
A Cosmic Ray Current-Driven Instability In Partially Ionised Media, Brian Reville, John Kirk, Peter Duffy, Stephen O'Sullivan
Articles
We investigate the growth of hydromagnetic waves driven by streaming cosmic rays in the precursor environment of a supernova remnant shock. It is known that transverse waves propagating parallel to the mean magnetic field are unstable to anisotropies in the cosmic ray distribution, and may provide a mechanism to substantially amplify the ambient magnetic field. We quantify the extent to which temperature and ionisation fractions modify this picture. Using a kinetic description of the plasma we derive the dispersion relation for a collisionless thermal plasma with a streaming cosmic ray current. Fluid equations are then used to discuss the effects …