![]() ![]() Since it is capable of detecting neutrinos from galactic supernovas, NOνA will form part of the Supernova Early Warning System. Its measurements in this area will complement other similar upcoming experiments, such as MINERνA, which also uses the NuMI beam. The NOνA near detector will be used to conduct measurements of neutrino interaction cross sections which are currently not known to a high degree of precision. NOνA, like MINOS, is well suited to detecting muon neutrinos and so will be able to refine our knowledge of θ 23. In addition to its primary physics goals, NOνA will be able to improve upon the measurements of the already measured oscillation parameters. The three experiments that have measured a value for θ 13, in deceasing order of sensitivity are Daya Bay in China, RENO in South Korea and Double Chooz in France, which use 1-2 km baselines, optimized for observation of the first θ 13-controlled oscillation maximum. While they cannot measure δ or the mass ordering, their measurement of the mixing angle is not dependent on knowledge of these parameters. Reactor experiments also have the ability to measure θ 13. The interpretation of Neutrinoless double beta decay experiments will also benefit from knowing the mass ordering, since the mass hierarchy affects the theoretical lifetimes of this process. Since matter effects are less pronounced both at lower energies and shorter baselines, it is unable to resolve the mass ordering for the majority of possible values of δ. It will have a 295 km baseline and will use lower energy neutrinos than NOνA, about 0.6 GeV. Like NOνA, it is intended to measure θ 13 and δ. Many future experiments that seek to make precision measurements of neutrino properties will rely on NOνA's measurement to know how to configure their apparatus for greatest accuracy, and how to interpret their results.Īn experiment similar to NOνA is T2K, a neutrino beam experiment in Japan similar to NOνA. Of the experiments currently running it has the broadest scope for making this measurement unambiguously with least dependence on the value of δ. NOνA can potentially resolve the mass hierarchy because it operates at a relatively high energy. If the measurements of NOνA and other future experiments continue to show θ 23 as maximal and θ 13 as minimal, it may suggest some as yet unknown symmetry of nature. And yet, of the three neutrino mixing angles, only θ 12 has been resolved as being neither maximal or minimal. In our current theory of physics, there is no reason why the neutrino mixing angles should have any particular values. Neutrino measurements are then an indirect way of studying physics at extremely high energies. ![]() Also, according to the Seesaw mechanism theory, the very small masses of neutrinos may be related to very large masses of particles that we do not yet have the technology to study directly. Knowing the value of the CP violating parameter δ will help us understand why the universe has a matter-antimatter asymmetry. Measuring them is a basic requirement for our understanding of physics. The neutrino masses and mixing angles are, to the best of our knowledge, fundamental constants of the universe. The mass ordering, similarly, can be determined because the neutrinos pass through the Earth, which, through the MSW effect, modifies the probabilities of oscillation differently for neutrinos and anti-neutrinos. The following year, T2K discovered the transition ν μ → ν e The parameter δ can be measured because it modifies the probabilities of oscillation differently for neutrinos and anti-neutrinos. In 2012, θ 13 was measured at Daya Bay to be non-zero to a statistical significance of 5.2 σ. Θ 23 and θ 12 have been measured to be non-zero by several experiments but the most sensitive search for non-zero θ 13 by the Chooz collaboration yielded only an upper limit. There is currently no compelling theoretical reason to expect any particular value of, or relationship between, these parameters. Assuming that three flavors of neutrinos participate in neutrino mixing, there are six variables that affect neutrino oscillation: the three angles θ 12, θ 23, and θ 13, a CP-violating phase δ, and any two of the three mass squared differences. Neutrino oscillation is parameterized by the PMNS matrix and the mass squared differences between the neutrino mass eigenstates.
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