The Origin of Cosmic Rays: Explosions of Massive Stars with Magnetic Winds and Their Supernova Mechanism
Abstract
One prediction of particle acceleration in the supernova (SN) remnants in the magnetic wind of exploding Wolf-Rayet and red supergiant stars is that the final spectrum is a composition of a spectrum E -7/3 and a polar cap component of E -2 at the source. This polar cap component contributes to the total energy content with only a few percent, but dominates the spectrum at higher energy. The sum of both components gives spectra which curve upward. The upturn was predicted to occur always at the same rigidity. An additional component of cosmic rays from acceleration by SNe exploding into the interstellar medium adds another component for hydrogen and for helium. After transport, the predicted spectra J(E) for the wind-SN cosmic rays are E -8/3 and E -7/3 the sum leads to an upturn from the steeper spectrum. An upturn has now been seen by the CREAM mission. Here, we test the observations against the predictions and show that the observed properties are consistent with the predictions. Hydrogen can be shown to also have a noticeable wind-SN component. The observation of the upturn in the heavy element spectra being compatible with the same rigidity for all heavy elements supports the magneto-rotational mechanism for these SNe. This interpretation predicts the observed upturn to continue to curve upward and approach the E -7/3 spectrum. If confirmed, this would strengthen the case that SNe of very massive stars with magnetic winds are important sources of Galactic cosmic rays.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2010
- DOI:
- arXiv:
- arXiv:1009.5592
- Bibcode:
- 2010ApJ...725..184B
- Keywords:
-
- acceleration of particles;
- cosmic rays;
- stars: Wolf-Rayet;
- supergiants;
- supernovae: general;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 15 pages, 2 figures. For publication in ApJ