The Sudbury Neutrino
Observatory (SNO) is a water Cherenkov detector dedicated to investigate
elementary particles called neutrinos. It is located 2070 m below
the surface in shaft number 9 of the INCO Creighton Nickel Mine
near Sudbury, Ontario.
All of the solar neutrino experiments conducted to date have
only detected only a fraction of the number of expected neutrinos
from the sun. This is called the Solar Neutrino Problem.
If the experiments are correct, then either our understanding of the Sun is seriously wrong, or 'neutrino oscillations' (which imply a non-zero neutrino mass) are reducing the number of detected electron neutrinos. |