Future studies of the neutrino and its mass
A number of experiments are planned or soon to be underway in neutrino physics; all of
these will be crucial tests for the newly-discovered neutrino mass.
Sudbury is revolutionary experiment, using a heavy-water target to measure not only the
flux of electron neutrinos from the Sun, but using a reaction channel not available in
light water, also the total number of neutrinos of all flavors. Clearly an eagerly awaited
experiment by all concerned with neutrino oscillations and neutrino mass.
Should SNO find the usual deficit of electron neutrinos, but the predicted total number
of neutrinos, it would be not only the solution to the 30-year old solar neutrino problem
but ironclad confirmation of neutrino oscillations and neutrino mass
If, on the other hand, SNO finds a neither enough electron neutrinos, nor the muon or
tau neutrinos these are thought to oscillate into, it would call for a fourth (exotic)
"sterile" neutrino and/or a re-examination of solar models.
The K2K ("KEK to Kamiokande") experiment will the first of several so-called
long-baseline experiments to attempt to replicate the atmospheric neutrino anomaly using a
more controlled neutrino beam from an accelerator. Two detectors positioned near the
beampipe will measure the muon neutrino flux as it emerges, and Super-Kamiokande, 250 km
distant, will look for disappearance of these muon neutrinos. K2K should begin operation
in 1999.
MINOS is a long-baseline experiment similar in concept to K2K. MINOS' advantages would
be a much more intense neutrino beam, and a longer neutrino flight distance to the Soudan-II experiment in Minnesota.
With the high luminosity and a fine-grained iron detector at the far end, MINOS may be
able to detect the production of tau particles by tau neutrinos - confirming the
hypotheses of neutrino mass and oscillation, as well as discovering (directly observing)
the tau neutrino as well!
