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View Full Version : We're Safe from Gamma Ray Bursts



Fraser
2006-May-11, 06:40 PM
SUMMARY: If a gamma ray burst happened near the Earth, it would make for a very bad day: our ozone layer would be stripped away, worldwide climate would change dramatically, and life would struggle to survive. Fortunately, it looks like they don't happen in galaxies like our Milky Way. Researchers have found that bursts tend to occur in small irregular galaxies that lack heavier chemical elements.

View full article (http://www.universetoday.com/am/publish/hst_earth_is_safe.html)
What do you think about this story? post your comments below.

antoniseb
2006-May-11, 07:03 PM
I've been seeing some hand-waving stuff lately about a special kind of supernova that an only happen in stars that start off with small amounts of elements heavier than Helium, and that these supernovae create lots of electron-positron pairs before going kablooey.

Does anyone have a pointer to a paper detailing how this can happen?

Don Alexander
2006-May-12, 02:46 PM
http://arxiv.org/abs/astro-ph/0509303

I don't know if this is what you are looking for?? It seems you are thinking of pair production supernova that disintegrate a star without leaving a remnant?

If so, this seems to be an old idea: Here's a paper from 1968, perhaps the one that started it all:

http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1968Ap%26SS...2...96F&db_key=AST&link_type=ARTICLE

(This should resolve into a scanned PDF document).

Well, concerning the actual article on Andy Fruchter's Nature paper:

Adrian Mellott recently pointed out that the milky way is accreting low-mass, low-metallicity dwarf galaxies all the time (news of more dwarf galaxies near the Milky Way was just recently reported on Universe Today) - and such galaxies would trigger star formation upon collision and could very well lead to GRBs...

Alex, Tautenburg, Germany