Mr. Yu Niinou (Kyoto Univ.) visit our group and give colloquium speech

Oct 17, 2008

“Lyman-alpha emission of long GRB host galaxies and the metallicity dependent GRB production”

Theoretical and observational studies suggest that long gamma-ray bursts (GRBs) preferentially occur in low-metallicity environment. Lyman-alpha equivalent width is a property of galaxies that is closely connected to the metal abundance of the galaxies, and hence Lyman-alpha emission luminosity of GRB host galaxies can provide us with an important clue to the metallicity dependence of long GRB production.

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Dr. George Chartas (Penn State Univ.) visit our group and give colloquium speech

Oct 10, 2008

“Inflows and Outflows from Supermassive Black Holes”

The current paradigm for the AGN phenomenon is a central engine that consists of an inflow of hot material accreting in the form of a disk onto a supermassive black hole. Recent observations also find powerful and high velocity ionized material outflowing from the black hole.

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