So many accounts say that neutrinos carry away about 99 percent of the energy from a 'traditional' supernova (giant star at end of its life), but what about a white dwarf detonated after accretion?
$\begingroup$
$\endgroup$
1
-
5$\begingroup$ "So many accounts" can you link to some? Providing sources (even if it's just a token sample) is much more helpful than only asserting their existence. $\endgroup$– user54772Commented Oct 11 at 15:04
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
No they don't. The proportion of energy released in neutrinos during a type Ia supernova is a thousand or more times lower as a proportion than for core collapse (type II) supernovae. It's worth noting that this is a theoretical prediction. There has been no opportunity to attempt the detection of neutrinos from a nearby type Ia supernova. Further discussion and a couple of references are given in https://physics.stackexchange.com/a/773353/43351 .
The fundamental reasons are in the method of energy release. Neutrinos are efficiently produced when quarks change flavours - when protons turn into neutrons or vice versa. A core collapse supernova derives its energy from gravitational potential energy. This can only be realised if about half the energy can escape. It does so because the collapse trigger of electron capture and neutronisation results in copious neutrino production in weak force moderated flavour-changing interactions - basically one high energy neutrino for every neutron created, and essentially all the core baryons are converted to neutrons.
Type Ia supernovae are powered by thermonuclear fusion of carbon and oxygen nuclei. These strong-force interaction processes produce nothing like the same number of neutrinos per nucleon, the majority of which would be produced indirectly in thermal processes (neutrino bremsstrahlung and the like).
