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A white dwarf formed by a supernova, possible?

  1. Jul 23, 2007 #1
    It is my general understanding that once a star goes supernova, the remnant core of the dead star will (always?) gravitationally contract into either a neutron star, or if massive enough, into a black hole.

    However, does current observation/model rule out a scenario whereupon a star goes supernova and blows off enough mass that the remaining core does not have sufficient mass to form a neutron star or black hole. Instead the remnant core contracts into a white dwarf?
    Last edited: Jul 23, 2007
  2. jcsd
  3. Jul 23, 2007 #2


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    The core wouldn't form a white dwarf because you wouldn't go supernova unless you had already burned all the fussionable fuel and were down to an iron core.
    You could possibly strip the atmosphere from a main sequence companion to leave it as a white dwarf.
  4. Aug 2, 2007 #3
    If I’m not mistaken, it is the collapse of the core into neutron-degenerate matter (which requires a large star in the region of 8 to 20 solar masses) which causes the supernova. Prior to the supernova, the iron core will probably resemble a white dwarf in size but because the fusion process has ceased due to the fact that iron is the most stable of elements, the outer layers would begin to exert massive pressure on the core and eventually, the electrons which have already filled every quantum state possible, have no where to go but into the protons that make up the iron nuclei (this releases a massive amount of neutrinos which is the calling card of the making of a neutron star). The planet sized core collapses to about 10-12 km in diameter in a fraction of a second. The outer layers then collapse inwards to fill the void, colliding with the surface of the neutron core and an effect akin to a hammer hitting a solid rubber ball takes place: the immediate outer layers recoil and pass through the outer layers of the star with extreme force causing the supernova. I believe the process of the core collapsing into neutron degenerate material is intrinsic with the supernova explosion.
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