Carbon detonation
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Carbon detonation is a violent re-ignition of thermonuclear fusion in a dead star, which produces Type Ia supernovae.
[edit] Process
A white dwarf undergoes carbon detonation only if it has a normal binary companion which is close enough to the dwarf star to dump sufficient amounts of matter onto the dwarf, expelled during the process of the companion's own late stage evolution.
If the companion supplies enough matter to the dead star, the white dwarf's internal pressure and temperature will rise high enough to fuse the previously unfusable carbon in the white dwarf's core. Carbon detonation generally occurs when the accreted matter pushes the white dwarf's mass past the Chandrashekhar limit of 1.44 solar masses.
Carbon detonation occurs much more rapidly than deflagration, which occurs at much lower velocities and is much less chaotic. Computer simulations show that the fusion front proceeds as a series of turbulent, expanding "bubbles" that exhibit Rayleigh-Taylor instability. [1]
The turbulence of the unstable fusion front makes it ragged, and the high surface area of the ragged front results in an extremely rapid "burn", known as a "thermonuclear flame". This rapid "burn" erupts explosively through the dwarf star's surface, which is seen as a type Ia supernova.
