Gamma-Ray Bursts - the brightest explosions in the Universe
by
T. Piran(Hebrew University)
→
Europe/Stockholm
FA32
FA32
Description
Gamma Ray Bursts (GRBs) are the brightest explosions observed in our Universe.
For a few seconds a GRBs over shines the gamma-ray (and in fact the whole EM) sky.
GRBs are the ultimate multi-messanger objects. Apart from gamma-rays GRBs emit EM
radiations in all ranges (from radio to TeV). It is also expected that they are strong sources
of gravitational radiation, Ultra high energy cosmic rays and neutrinos. I review the prospects
of detection of those multi-messenger signals. Among the most interesting questions concerning
GRBs is, of course, what is their origin. Simple energetic estimates show that they must
involve the birth of a compact object. Currently it is widely believed that long GRBs are
produced by Collapsars and that short GRBs are produced by neutron star mergers.
I examine the evidence for these ideas providing a new evidence for the Collapsar model
but also show that there must be a third population of GRB that have a different origin than
those two.