On 21/10/2010 16:37, john wrote:
On Oct 21, 8:47 am, Sam wrote:
On 10/21/10 2:01 AM, john wrote:





On Oct 20, 8:17 pm, Sam wrote:
http://news.sciencemag.org/scienceno...ot-black-hole-...

"... the black-hole's progenitor was actually the more massive of the
two, tipping the scales at 97 solar masses. But the big star fused its
hydrogen and helium into heavier elements with lightning speed,
expelling gigantic solar winds. The companion star lapped up gobs of
that expelled material, growing quickly to its current size. When the
progenitor star had no more helium to fuse, it collapsed into a black
hole—which we now see is pulling matter back in from the companion star
at a furious clip".

That's a black hole like I'm an astronaut.How do neutrinos fit in,
Sam?
Do they do anything?

john

Neutrinos pour out of the core of the star undergoing nuclear fusion.
And some of those neutrinos go into the black hole. You should take
the time to do some self-education WRT neutrinos, John.

Background
http://en.wikipedia.org/wiki/Neutrino- Hide quoted text -

- Show quoted text -

I didn't ask 'where do they go?', Sam.

I asked, 'do they do anything?'.

What is their role? Why are they given
off in fusion events?

That is what the rules of QCD require. Conservation laws of a sort.

The tricky question is determining their rest mass accurately enough.
There is still a question about the total neutrino flux from the sun and
the proportion reaching the Earth based observatories.

They are also given off in supernovae events and the various terrestrial
neutrino observatories have seen neutrino flashes.
http://www.spacedaily.com/news/supernova-04g.html

It is hoped to provide early warning for looking at supernovae on the
rising light curve.

Regards,
Martin Brown