9 April 2001Joint Physics &CfA Colloquium

Note Special Location & Time: Monday, April 9th at 4:30 PM in Jefferson 250

Title: Gamma-Ray Bursts: The Brightest Explosions in the Universe

Speaker: Shri Kulkarni

Abstract: A few times a day the sky is lit up by brilliant flashes of gamma-rays. Though discovered more than three decades ago, astronomers were in the dark about the origin of these bursts. The speaker will present evidence that decisively demonstrate that many gamma-ray bursts (GRB) are located at cosmological distances. These bursts are then the most brilliant astronomical objects. There are good reasons to suspect that GRBs may well be responsible for the highest energy cosmic rays in the Universe and are appearing to be attractive targets for gravitational wave interferometers, TeV and neutrino telescopes. It has been speculated that GRBs mark the end states of massive stars and the birth of spinning black holes or highly magnetized neutron stars from which the energy to fuel these brilliant bursts is somehow extracted. The talk will end with a presentation of a concept of a dedicated facility to study these engimatic objects as well use GRBs to probe star formation and intergalactic medium in the early Universe.

A special lunch with the students will be held on Monday, May 7th at 12:30 in A-101.