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Dogunut Star

  1. Jul 20, 2010 #1
    Can an accretion disk get dense enough to start fusion? How dense does something have to be in order to start fusion?

    Does it depend on the material?

    is there a way of measuring the density of accretion disks?
  2. jcsd
  3. Jul 21, 2010 #2


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    It takes about 100 jupiter masses to trigger hydrogen fusion. This is the lower limit for a brown dwarf star. Small is not bad, though, such a star can burn steadily for 100 billion years.
  4. Aug 1, 2010 #3
    Yes, but the accretion disk will not form a disk-shaped star- it will fail to reach a stable equilibrium, like stars do, and instead just burn off super fast. This event is known as a nova.

    If the accretion disk gets massive enough that a white dwarf passes the Chandrasekhar limit, carbon fusion occurs and the event is known as a Type 1A supernova.
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