Title:  Cosmic-Ray Acceleration in Supernova Remnants

Dr. Patrick Slane
Harvard-Smithsonian CfA

Abstract:

The Milky Way is infused with a population of energetic particles whose energy density rivals that of the magnetic fields and starlight in the Galaxy. Such "cosmic rays" are observed at energies far in excess of those attainable in terrestrial particle accelerators, yet their exact origin remains poorly understood. At energies up to the "knee" in the spectrum at about 1 PeV, cosmic rays are thought to originate from within the Galaxy. Based on overall energetics as well as the presence of a viable mechanism for shock acceleration of particles, it has long been suspected that supernova remnants may be a major source of cosmic rays. Results from a wide range of multiwavelength studies of supernova remnants have now provided strong evidence for acceleration of particles to extremely high energies. Here I review the observational signatures for such particle acceleration, and summarize recent X-ray and gamma-ray studies, as well as modeling efforts, that are providing a multi-faceted approach to our understanding of such particle acceleration in supernova remnants, and the source of Galactic cosmic rays.