Supernovae, pulsars, and gamma-ray bursts: A unified picture

A scenario is proposed that explains both the observed high pulsar velocities and extragalactic gamma-ray bursts (GRBs). The model involves an ultrarelativistic jet from a supernova (SN) that produces a GRB and its afterglow, whose characteristics are similar to an isotropic fireball GRB perhaps with some differences at late times in the afterglow once some significant transverse diffusion has occurred. The timescales and many other properties of GRBs and their afterglows in this model are consistent with observations. GRBs in this model have special intrinsic properties, which can either falsify or prove this model unambiguously by observations. The most direct proof is the detection of an SN about the same time as the luminous GRB event. Most GRBs and SNe are expected occur at moderate redshift (z similar to 1-3), if they follow the observed universal star formation history, as implied in this model. Searching for GRB/SN associations is a challenge because the majority of the SNe will be faint. Some additional, dramatic observable consequences are predicted, which can also be utilized to test the model.