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m1omg
2009-Jan-04, 03:06 PM
What would happen if two typical carbon-oxygen white dwarfs collided?How big a bang would it make?Since type Ia supernovas are caused by buildup of accreted matter from a companion star on the surface of an carbon-oxygen white dwarf, causing carbon detonation in the white dwarf, I would imagine that two carbon-oxygen white dwarfs colliding would produce even bigger bang.Or would they just merge into a bigger white dwarf or a neutron star, causing an explosion, but just because of the collision kinetic energy and the explosion would not be powerful enough to tear the white dwarfs apart??

eburacum45
2009-Jan-04, 04:21 PM
Have you listened to this Universe Today podcast, m1omg?
http://www.universetoday.com/2007/11/09/podcast-when-white-dwarfs-collide/

Mike Smith
2009-Jan-04, 05:07 PM
It seems this might just happen every now and then, a recent publication with some evidence for a C-O merger.

Hicken,~M., et al. The luminous and carbon-rich supernova 2006gz: A double degenerate merger? Astrophysical Journal Letters vol. 669, pp. L17-L20 (2007).

Mike Smith
2009-Jan-04, 05:12 PM
When such a merger happens an explosion becomes inevitable if the total mass is over the Chandrasekhar limit, which is about 1.4 time our solar mass. Such mergers may become problematic for the Kirshner and Perlmutter groups because their distance measurements are based up the explosions of supernova always occurring with a unique mass of about 1.4 solar. So if two white C-O dwarfs with each solar mass = our sun merge, the resulting explosion will appear much closed than it actually is (was).:confused: