Prof. Gerry Brown
Department of Physics
State University of New York, Stony Brook.

I argue that the long, many-second gamma ray bursts are powered by the rotational energy of a high-mass black hole, and will discuss from binary evolution why the black hole is rotating so fast. Part of the rotational energy is deposited in the accretion disc, composed of the material from the outer part of the massive star in which the black hole is formed. The resulting very energetic explosion of this disc has been seen both optically and in Fe lines. Relics of gamma ray bursters in the black hole transient sources will be discussed.