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PRODID:UW-Madison-Physics-Events
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SEQUENCE:0
UID:UW-Physics-Event-1467
DTSTART:20091016T210000Z
DURATION:PT1H0M0S
DTSTAMP:20260506T172208Z
LAST-MODIFIED:20090902T133941Z
LOCATION:2241 Chamberlin Hall (coffee and cookies at 3:30 pm)
SUMMARY:Gamma Ray Bursts and the Birth of Black Holes\, Physics Depart
 ment Colloquium\, Neil Gehrels\, NASA Greenbelt\, U-Maryland\, Penn St
 ate U
DESCRIPTION:Black holes have been predicted since the 1940's from solu
 tions of Einstein's general relativity field equation. There is strong
  evidence of their existence from astronomical observations\, but thei
 r origin has remained an open question of great interest.  Gamma-ray b
 ursts may the clue. They are powerful explosions\, visible to high red
 shift\, and appear to be the birth cries of black holes. The Swift and
  Fermi missions are two powerful NASA observatories currently in orbit
  that are discovering how gamma-ray bursts work.  Evidence is building
  that the long and short duration subcategories of GRBs have very diff
 erent origins: massive star core collapse to a black hole for long bur
 sts and binary neutron star coalescence to a black hole for short burs
 ts. The similarity to Type II and Ia supernovae originating from young
  and old stellar progenitors is striking. Bursts are tremendously lumi
 nous and are providing a new tool to study the high redshift universe.
  One Swift burst at z=8.3 is the most distant object known in the univ
 erse. The talk will present the latest gamma-ray burst results from Sw
 ift and Fermi and will highlight what they are teaching us about black
  holes and jet outflows.
URL:https://www.physics.wisc.edu/events/?id=1467
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