BGU Physics Department
Colloquium, Dec. 27th, 2012
Gamma-Ray Bursts: the Quest for the Progenitors
Elena Pian, INAF,
Trieste Astronomical Observatory, Trieste, Italy and Scuola Normale
Superiore, Pisa, Italy
Ever since the multi-wavelength counterparts of Gamma-Ray
Bursts (GRBs) have been detected, more than 15 years ago, new mysteries and
unknowns have taken the place of old questions and the field has become a
laboratory for a vast range of astrophysical topics, primarily stellar
evolution and explosions. Identifying GRB progenitors and their evolutionary
paths is one of the biggest outstanding problems about these sources. While
the properties of short-duration GRBs and their host galaxies suggest
compact binary star mergers as potential progenitors (but no direct
observation has proved it), long duration GRBs are unambiguously associated
with stripped-envelope core-collapse supernovae. These are a subset of
so-called Type Ic supernovae with very high kinetic energies, but the
mechanism by which such powerful supernovae produce relativistic jets is not
clear. I will review the state-of-the-art of the observations and the
fundamental problems that are still currently open.