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VERSION:2.0
CALSCALE:GREGORIAN
PRODID:UW-Madison-Physics-Events
BEGIN:VEVENT
SEQUENCE:0
UID:UW-Physics-Event-1358
DTSTART:20081111T213000Z
DURATION:PT1H0M0S
DTSTAMP:20260506T200046Z
LAST-MODIFIED:20081110T204215Z
LOCATION:6515 Sterling Hall
SUMMARY:Breakout: High-Energy Transients from Supernovae and the Myste
 ry of the Dim GRBs\, Astronomy Colloquium\, Chris Matzner\, University
  of Toronto
DESCRIPTION:Since 1998 is has been clear that some long-duration gamma
 -ray bursts come from broad-lined type Ic supernovae -- energetic expl
 osions of bare stellar cores. For bright\, variable GRBs observed at c
 osmological distances\, this means that an ultra-relativistic jet must
  sweep aside the star's envelope before beaming at Earth. However\, a 
 much more populous class of dim bursts\, which lack evidence for beami
 ng or highly relativistic flow\, has recently become apparent. Are the
 se produced by off-axis jets\, or shock breakout? I shall review these
  two physical models\, and argue that dim GRBs and related x-ray trans
 ients reveal an unexpected diversity of pre-explosion stellar mass los
 s behavior.
URL:https://www.physics.wisc.edu/events/?id=1358
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