Etudes des proprietes des neutrinos dans les contextes ...

tel-00450051, version 1 - 25 Jan 2010
CP-violating phase. Many experiments are on the verge to learn more about θ13.
2.5.1 Current and near-future experiments
The precision on sin 2 2θ13 can be improved over previous experiments by: using
larger detectors to increase statistics, locating the detectors deeper underground
to suppress background, using ”near” and ”far” detectors to suppress the systematic
uncertainties related to the anti-neutrino flux from reactors. The discovery
of a non-zero θ13 will define the strategy to follow for future accelerator-based
experiments to measure the value of the Dirac phase.
Double-Chooz
Double-Chooz [13] will improve the Chooz result. This requires an increase in
the statistics, a reduction of the systematic error below one percent, and a careful
control of the backgrounds. Therefore, Double Chooz will use two identical
detectors, one at 400 m and another at 1.05 km distance from the Chooz nuclear
cores. The plan is to detect the first anti-neutrino before the end of 2009 with
one detector and to have both detectors operating by the middle of 2011. With
such a scenario Double Chooz will reach a sin 2 (2θ13) sensitivity of 0.06 after 1
year of operation with 1 detector, and 0.03 after 3 years of operation with both
detectors.
Daya Bay
The Daya Bay Reactor Neutrino Experiment [70] is designed to measure the
mixing angle θ13 using antineutrinos produced by the reactors of the Daya Bay
Nuclear Power Plant and the Ling Ao Nuclear Power Plant. The goal of the Daya
Bay experiment is a measurement of sin 2 (2θ13) to 0.01 or better.
T2K (Tokai to Kamioka)
Contrary to Double-Chooz or Daya Bay which are looking for the disappearance
of electron anti-neutrinos produced by nuclear power plants, the T2K experiment
[77] is going to measure the appearance of νe neutrino beam from a νµ beam.
The J-PARC facility will produce this intense beam of muon neutrinos directed
towards the Super-Kamiokande detector (295 Km away). Precise measurements
of the other neutrino mixing parameters ∆m 2 32 and θ23 are another aim of the
experiment. Future upgrades to T2K could yield measurement of δ by comparing
oscillations of neutrinos to those of antineutrinos.
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