Solar Neutrinos


What about those funny neutrino things? What is a neutrino?

We can calculate the mean free path of a neutrino inside the Sun to be

Once created, they nearly all immediately escape from the Sun. If we can see them, we can see into the very center of the Sun.

How do we detect these neutrinos?


The Chlorine Experiment
  This experiment finds 2.6 +/- 0.2 SNUs (solar neutrino units -- basically 10-36 reactions/atom/day). This is like 1 reaction every two days. But theoretical models of the Sun predict 7.7 +/- 1.1 SNUs.

We don't see enough neutrinos! This is the Solar Neutrino Problem.

What's the solution?