The Neutrino Test

• Since the -rays released in the center do not travel out of the core directly, do we have a way to ``see'' into the center of the Sun and test our little theory about H-fusion and high temperatures?
  1. GONG and SOHO measurements of the resonant frequencies that the Sun ``rings" at.

  2. Our little friend the .

• Remember that because they have no charge and are essentially massless, have a very tiny ``cross-section'' for interacting with everything.

• The Sun produces around per second.
  

• Since pass right through the Sun and everything else, they give a direct view of what goes on in the center of the Sun for people with neutrino sensitive eyes.
  

• Starting about 30 years ago they decided to search for solar .
  1. Fill up a swimming pool in an old gold mine with cleaning fluid.

  2. Wait for the 1 out of solar expected to interact with a chlorine atom and become an argon atom.

  3. Drain the swimming pool and count the argon atoms.

• The answer? Too few solar neutrinos by about a factor of 2!

• After many additional experiments and other tests of the ``Standard Solar Model'' it looks like what we get from this is something new about neutrino physics - the stellar models look OK.

There are some something interesting implications of our picture of how the Sun derives its Luminosity.

• The Universe is changing in one direction - H He.

• The Sun, and other stars too, will eventually run out of fuel.

  We calculated the lifetime of the Sun as a H-fusion-powered object, but this assumed the entire Sun was pure Hydrogen and that ALL the hydrogen could be fused to Helium. In fact, by the time about 10% of the Hydrogen is fused to Helium the Sun will change its structure and no longer be a main-sequence star.

• We can already figure out the rough main-sequence lifetimes of stars of different mass.

  A star has a central temperature of and luminosity of .

  We know that the Fuel of stars is Mass and the Rate of Fuel Consumption is the Luminosity. So the star would be expected to live 10 times longer based on its extra fuel, but, 1/40000 less long based on its fuel consumption:

  Similarly a stars with would have a main-sequence lifetime that was: