Page "Gamma-ray burst" Paragraph 30

The massive-star model probably does not explain all types of gamma-ray burst.

There is strong evidence that some short-duration gamma-ray bursts occur in systems with no star formation and where no massive stars are present, such as elliptical galaxies and galaxy halos.

The favored theory for the origin of most short gamma-ray bursts is the merger of a binary system consisting of two neutron stars.

According to this model, the two stars in a binary slowly spiral towards each other due to the release of energy via gravitational radiation until the neutron stars suddenly rip each other apart due to tidal forces and collapse into a single black hole.

The infall of matter into the new black hole produces an accretion disk and releases a burst of energy, analogous to the collapsar model.

Numerous other models have also been proposed to explain short gamma-ray bursts, including the merger of a neutron star and a black hole, the accretion-induced collapse of a neutron star, or the evaporation of primordial black holes.