Dr. Judy Racusin (NASA/GSFC) visit our group and give colloquium speech

Oct 22, 2010

“Fermi-LAT Gamma-ray Bursts and Insight from Swift”

A new revolution in Gamma-ray Burst (GRB) observations and theory has begun over the last two years since the launch of the Fermi Gamma-ray Space Telescope.  The new window into high energy gamma-rays opened by the Fermi-Large Area Telescope (LAT) is providing insight into prompt emission mechanisms and possibly also afterglow physics.  

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Dr. Weihua Lei (Huazhong Univ. of Science and Technology, China) visit our group and give colloquium speech

Oct 1, 2010

The central engine of gamma-ray bursts: Blandford-Znajek Process and neutrino-antineutrino annihilation”

The nature of the central engine of gamma-ray bursts (GRBs) has been one of the main puzzles of astrophysics, which is widely believed to be related to the merger of two neutron stars, the merger of neutron star and black hole, or the collapse of a supermassive star. All of these scenarios involve a rotating black hole with a hyper accretion disk or torus, from which energy is extracted for powering GRBs by neutrino-antineutrino annihilation or by extracting rotational energy from the black hole or disk via large scale magnetic field.

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