Journal Article

A common envelope binary star origin of long gamma-ray bursts

Christopher A. Tout, Dayal T. Wickramasinghe, Herbert H.-B. Lau, J. E. Pringle and Lilia Ferrario

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 410, issue 4, pages 2458-2462
Published in print February 2011 | ISSN: 0035-8711
Published online January 2011 | e-ISSN: 1365-2966 | DOI: http://dx.doi.org/10.1111/j.1365-2966.2010.17622.x
A common envelope binary star origin of long gamma-ray bursts

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics

GO

Show Summary Details

Preview

The stellar origin of γ-ray bursts can be explained by the rapid release of energy in a highly collimated, extremely relativistic jet. This in turn appears to require a rapidly spinning highly magnetized stellar core that collapses into a magnetic neutron star or a black hole within a relatively massive envelope. They appear to be associated with Type Ib/c supernovae but, with a birth rate of around 10−6 to 10−5 yr−1 per galaxy, they are considerably rarer than such supernovae in general. To satisfy all these requirements we hypothesize a binary star model that ends with the merging of an oxygen/neon white dwarf with the carbon/oxygen core of a naked helium star during a common envelope phase of evolution. The rapid spin and high magnetic field are natural consequences of such a merging. The evolution that leads to these progenitors is convoluted and so naturally occurs only very rarely. To test the hypothesis we evolve a population of progenitors and find that the rate is as required. At low metallicity we calculate that a similar fraction of stars evolve to this point and so would expect the γ-ray burst rate to correlate with the star formation rate in any galaxy. This too is consistent with observations. These progenitors, being of intermediate mass, differ radically from the usually postulated high-mass stars. Thus we can reconcile observations that the bursts occur close to but not within massive star associations.

Keywords: binaries: close; gamma-ray burst: general; stars: neutron; white dwarfs

Journal Article.  4725 words. 

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.