Journal Article

Escaping the accelerator: how, when and in what numbers do cosmic rays get out of supernova remnants?

L. O'C. Drury

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 415, issue 2, pages 1807-1814
Published in print August 2011 | ISSN: 0035-8711
Published online July 2011 | e-ISSN: 1365-2966 | DOI: https://dx.doi.org/10.1111/j.1365-2966.2011.18824.x
Escaping the accelerator: how, when and in what numbers do cosmic rays get out of supernova remnants?

Show Summary Details

Preview

The escape of charged particles accelerated by diffusive shock acceleration from supernova remnants is shown to be a more complex process than normally appreciated. Using a box model it is shown that the high-energy end of the spectrum can exhibit spectral breaks even with no formal escape as a result of geometrical dilution and changing time-scales. It is pointed out that the bulk of the cosmic ray particles at lower energies must be produced and released in the late stages of the remnant's evolution, whereas the high-energy particles are produced early on; this may explain recent observations of slight compositional variations with energy. Escape resulting from ion–neutral friction in dense and partially ionized media is discussed briefly and some comments made on the use of the so-called ‘free-escape boundary conditions’. Finally, estimates are made of the total production spectrum integrated over the life of the remnant.

Keywords: acceleration of particles; cosmic rays; ISM: supernova remnants

Journal Article.  6859 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.