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Fraser
2007-Jul-11, 07:56 PM
When a star with at least 8 times the mass of our Sun detonates as a supernova, it leaves behind a neutron star. This tiny object has the mass of a star, but it's compressed down to a ball only 10 km (6 miles) across - its protons and electrons have been compressed together to form neutrons. ...

Read the full blog entry (http://www.universetoday.com/2007/07/11/supernova-remnant-may-actually-have-a-partner/)

trinitree88
2007-Jul-12, 12:14 PM
When a star with at least 8 times the mass of our Sun detonates as a supernova, it leaves behind a neutron star. This tiny object has the mass of a star, but it's compressed down to a ball only 10 km (6 miles) across - its protons and electrons have been compressed together to form neutrons. ...

Read the full blog entry (http://www.universetoday.com/2007/07/11/supernova-remnant-may-actually-have-a-partner/)

Fraser. It's a little more subtle than compressing protons and electrons into neutrons. If that were true, diamond anvil presses might make black holes over time.
The core that neutronizes has a combination of the three parameters for fusion, time, temperature and density that allows conversion of protons into neutrons (weak interaction) in violent collisions. The process produces a high flux of W+ particles, which almost immediately decay to positrons and neutrinos. The neutrinos stream away (mostly, but not without consequence), and the positrons annihilate the electrons (they are not "squeezed" into the protons). The annihilation energy makes gamma rays.Other gammas are made from the jets that escape the ejecta.
So the quartet is core collapse to pulsar with gravitational wave emitted (requires asymmetric phenomenology), neutrino burst, GRB.

Adding an electron to a proton by "squeezing" will not make a neutron under any pressure without the simultaneous "squeezing" in of an electron-type antineutrino, as that is what you get when a free neutron decays radioactively in ~ 1000 seconds. Pete.

Northwind
2007-Jul-13, 01:56 AM
Supernova are the result of stellar fissioning. :lol:

Any other super/novas with a binary partner?

trinitree88
2007-Jul-13, 12:15 PM
Supernova are the result of stellar fissioning. :lol:

Any other super/novas with a binary partner?

Northwind. Fission refers to splitting, like a fissure in a rock, or glacier. In nuclear terms it's the big heavy nuclei that fission...like uranium, plutonium, thorium, into lighter fragments.
Supernova have no heavy elements like that when they go off. They produce energy in the same basic joining together of lighter nuclei that generally runs the star's energy budget (fusion). It's just that they are unstable, and decide to use a huge amount of fuel at once. The explosion produces a very strong Northwind indeed.
There's also more than a touch of gravitational binding energy in core collapse Supes.
pete

Northwind
2007-Jul-16, 03:25 AM
Fission refers to splitting, like a fissure in a rock, or glacier

yep, I know.