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Supernovae are exploding stars. These stellar explosions are
responsible for creating all the elements heavier than iron and for
distributing the elements synthesized throughout the star's lifetime
to the interstellar medium. The CfA Supernova Group uses various
telescopes (Mount Hopkins, MMT, Magellan) to study supernovae of all
types, both in nearby and distant galaxies.
Supernovae come in two distinct physical flavors. Type Ia supernovae
result from a thermonuclear runaway in a carbon and oxygen
White Dwarf star that reaches a critical mass of 1.4 solar
masses. With a peak luminosity of 9 billion times that of the Sun,
Type Ia supernovae can be seen out to a sizeable fraction of the
visible Universe, and hence serve as distance indicators on
cosmological scales. The CfA Supernova Group has been instrumental in
establishing the foundations of cosmology with Type Ia supernovae (see
also The Accelerating
Universe).
Supernovae also occur when massive stars run out of fuel to support
their own weight. At this stage the star's dense iron core
collapses and then bounces, driving a powerful shock wave which
unbinds the star. The CfA Supernova Group has used these
"core-collapse" supernovae both as extragalactic distance indicators
(Type II supernovae), to probe the connection between Type Ib/c
supernovae and gamma-ray burstsm and to understand the various conditions
under which very massive stars die.
Project Links
The CFA Supernova web page
CfA Supernova Publications
Supernova Identification at the CfA
Supernova Follow-up at the CfA
Infrared Supernova Follow Up With PAIRITEL
The SN 1987A HST research page (SAINTS/SINS)
High-Z SN Search Team that discovered the Accelerating Universe
The ESSENCE Supernovae
cosmology project
People
Robert Kirshner,
Edo Berger,
Alicia Soderberg,
Peter Challis,
Stephane Blondin,
Michael Wood-Vasey,
Malcolm Hicken,
Andrew Friedman,
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