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UID:UW-Physics-Event-1990
DTSTART:20101118T213000Z
DTEND:20101118T230000Z
DTSTAMP:20260422T204548Z
LAST-MODIFIED:20100930T145538Z
LOCATION:4421 Sterling Hall
SUMMARY:The Diverse Fates of Single and Binary Massive Stars\, Astrono
 my Colloquium\, Nathan Smith\, University of Arizona
DESCRIPTION:Core-collapse supernovae (SNe) are bright\, and therefore 
 have the<br>
\npotential to reveal details about the outcome of stella
 r evolution at large distances and different environments.  However\, 
 our ability to theoretically predict which initial masses (and metalli
 cities) produce which specific types of SNe they produce (e.g.\, Types
  Ib\, Ic\, II-P\,II-L\, IIn\, IIb) is in rather miserable shape. This 
 has critical implications for understanding the origin of long-duratio
 n GRBs\, for example\, which have been linked to Type Ic SNe.  Observa
 tional input about the diverse end fates of massive stars helps this s
 ituation on two main fronts: 1. A growing number of direct detections 
 of progenitor stars at the locations of SNe in archival pre-explosion 
 data\, mostly from HST\, provides important links between the type of 
 SN and the star's initial mass.  2.  We now have reasonably good estim
 ates about the relative fractions of different SN subtypes from the fi
 rst decade of the Lick Observatory SN Search\, allowing us to quantify
  what fraction of massive stars explode as which types of SN. Combinin
 g these two constraints\, I will discuss the implications for the rang
 e of initial stellar masses that correspond to each type of SN.  A key
  result (long suspected but now quantified) is that simple predictions
  of single-star stellar evolution models cannot be reconciled with the
  observed SN fractions\, and that close binary evolution must be a pri
 mary agent responsible for SNe that have lost their H envelopes.  Even
  accounting for this binary evolution (which has its own pitfalls)\, t
 he remaining single-star progenitors contradict single-star evoution m
 odels\, with some surprising implications.  Time permitting\, I will d
 iscuss some of the strange things that can occur in massive evolved bi
 nary systems -- especially one of them.
URL:https://www.physics.wisc.edu/events/?id=1990
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