Long and short gamma-ray bursts, and the pulsar kicks

One of the mysteries that surround gamma-ray bursts (GRB) is the origin of two classes of events: long and short GRB. The short GRB are similar to the first second of a long GRB. We suggest that the short bursts are interrupted long bursts, we point out a plausible mechanism for the interruption, and we explain the observed time scales. The supernova-like central engine may contain a neutron star or a black hole surrounded by an accretion disk and jets. In the case of a neutron star, the same mechanism that is responsible for the pulsar kicks can disrupt the central engine, thus producing an interrupted, short GRB. If a black hole is produced, the absence of the kick ensures the long duration of the GRB. The time delay of the kick and the absence of the kick for a black hole are natural consequences of a model based on neutrino oscillations.