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Himanshu Raj
2007-Jan-01, 05:44 AM
Gamma-ray bursts are the most powerful explosions in the Universe, yet they are random and fleeting, never appearing in the same place twice. The only way to study them in detail is to observe them as quickly as possible with the most powerful telescopes we have.


http://www.eurekalert.org/multimedia/pub/web/2740_web.jpg


This burst -- unlike all other long gamma-ray bursts seen at close distance --was not accompanied by a supernova, for reasons scientists do not yet fully understand.

As with other gamma-ray bursts, this hybrid burst is likely signaling the birth of a new black hole. It is unclear, however, what kind of object or objects exploded or merged to create the black hole or, perhaps, something even more bizarre. The hybrid burst exhibits properties of the two known classes of gamma-ray bursts, characterized as "long" and "short," yet has other features that cannot be explained.

While scientists remain undecided on whether this was a long short burst from a merger or a long burst from a star explosion that, for some unknown reason, did not produce a supernova, most conclude that some new process must be at play: either the model of mergers creating second-long bursts needs a major overhaul, or the progenitor star from an explosion is intrinsically different from the kind that makes supernovae.

trinitree88
2007-Jan-13, 09:52 PM
Gamma-ray bursts are the most powerful explosions in the Universe, yet they are random and fleeting, never appearing in the same place twice. The only way to study them in detail is to observe them as quickly as possible with the most powerful telescopes we have.


http://www.eurekalert.org/multimedia/pub/web/2740_web.jpg


This burst -- unlike all other long gamma-ray bursts seen at close distance --was not accompanied by a supernova, for reasons scientists do not yet fully understand.

As with other gamma-ray bursts, this hybrid burst is likely signaling the birth of a new black hole. It is unclear, however, what kind of object or objects exploded or merged to create the black hole or, perhaps, something even more bizarre. The hybrid burst exhibits properties of the two known classes of gamma-ray bursts, characterized as "long" and "short," yet has other features that cannot be explained.

While scientists remain undecided on whether this was a long short burst from a merger or a long burst from a star explosion that, for some unknown reason, did not produce a supernova, most conclude that some new process must be at play: either the model of mergers creating second-long bursts needs a major overhaul, or the progenitor star from an explosion is intrinsically different from the kind that makes supernovae.


Himanshu Raj. Actually there are several known soft gamma ray repeaters, SGR's..so they do sometimes repeat at the same location.Pete.