Abstract:
The stellar origin of gamma-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 magnetised stellar core that collapses into a magnetic neutron star or a black hole within a relatively massive envelope. 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 at the end of a common envelope phase of evolution. The rapid spin and high magnetic field are a natural consequence 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.
Coffee and tea will be served 20 minutes prior to the seminar.