Speaker
Dr
Justin Evans
(University College London)
Description
The MINOS experiment utilizes the NuMI beam of muon neutrinos to study the
phenomenon of neutrino oscillations. Neutrinos are sent over a baseline of
735 km, with a detector near the production point at Fermilab and one at
the Soudan underground laboratory in northern Minnesota. By measuring the
disappearance characteristic of oscillations, MINOS has made the best
measurement of the atmospheric neutrino mass splitting to date. By looking
for electron neutrino appearance, a limit has been placed on the the
mixing angle sin^2(2*theta_13) of < 0.29 at 90% c.l. (for delta_CP = 0 and
normal mass hierarchy). A study of neutral current interactions has
allowed limits to be placed on the existence of additional, sterile
neutrino flavours beyond the three of the standard oscillation model.
Using the 7% muon antineutrino component of the beam, the first direct
observation of muon antineutrinos in a long baseline experiment has been
made, along with direct limits on the antineutrino oscillation parameters.
In September 2009, the current in the NuMI focusing horns will be
reversed to begin running with a dedicated antineutrino beam. This will
allow the first precision measurements of the atmospheric-regime
antineutrino oscillation parameters, an important test of CPT-invariance
in the neutrino sector.
Primary author
Dr
Justin Evans
(University College London)
