分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-09-17
摘要: If the tau neutrino is as heavy as 10 MeV which may have certain astrophysical implications, the neutrino mass pattern is studied so as to accommodate the new oscillation observations. It predicts that the electron neutrino has Marjorana mass around 0.05 eV. A supersymmetric model is described to realize the above scenario.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-09-17
摘要: The three active light neutrinos are used to explain the neutrino oscillations.The inherently bi-large mixing neutrino mass matrix and the Fritzsch type,bi-small mixing charged lepton mass matrix are assumed. By requiring the maximal #23;μ −#23;#28; mixing for the atmospheric neutrino problem and the mass-squared difference approperiate for the almost maximal mixing solution to the solar neutrino problem, the following quantities are predicted: the #23;e−#23;μ mixing, Ve3, CP violation in neutrino oscillations, and the effective electron-neutrino mass relevant to neutrinoless double beta decays.
分类: 物理学 >> 核物理学 提交时间: 2016-09-09
摘要: We report a new measurement of electron antineutrino disappearance using the fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×105 GWth-ton-days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six 241Am-13C radioactive calibration sources reduced the background by a factor of two for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin22θ13 and |Δm2ee| were halved as a result of these improvements. Analysis of the relative antineutrino rates and energy spectra between detectors gave sin22θ13=0.084±0.005 and |Δm2ee|=(2.42±0.11)×10−3 eV2 in the three-neutrino framework.
分类: 物理学 >> 核物理学 提交时间: 2016-09-05
摘要: The Daya Bay Reactor Neutrino Experiment discovered an unexpectedly large neutrino oscillation related to the mixing angle θ13 in 2012. This finding paved the way to the next generation of neutrino oscillation experiments. In this article, we review the history, featured design, and scientific results of Daya Bay. Prospects of the experiment are also described.