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We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline (BVLB) neutrino oscillation experiment consisting of a conventional horn produced low energy wide band beam and a detector of 500 kT fiducial mass with modest requirements on event recognition and resolution. Such an experiment is intended primarily to determine CP violating effects in the neutrino sector for 3-generation mixing. We analyze the sensitivity of such an experiment. We conclude that this experiment will allow determination of the CP phase $delta_{CP}$ and the currently unknown mixing parameter $theta_{13}$, if $sin ^2 2 theta_{13} geq 0.01$, a value $sim 15$ times lower than the present experimental upper limit. In addition to $theta_{13}$ and $delta_{CP}$, the experiment has great potential for precise measurements of most other parameters in the neutrino mixing matrix including $Delta m^2_{32}$, $sin^2 2theta_{23}$, $Delta m^2_{21}times sin 2 theta_{12}$, and the mass ordering of neutrinos through the observation of the matter effect in the $ u_mu to u_e$ appearance channel.
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Neutrino oscillations in matter provide a unique probe of new physics. Leveraging the advent of neutrino appearance data from NOvA and T2K in recent years, we investigate the presence of CP-violating neutrino non-standard interactions in the oscillation data. We first show how to very simply approximate the expected NSI parameters to resolve differences between two long-baseline appearance experiments analytically. Then, by combining recent NOvA and T2K data, we find a tantalizing hint of CP-violating NSI preferring a new complex phase that is close to maximal: $phi_{emu}$ or $phi_{etau}approx3pi/2$ with $|epsilon_{emu}|$ or $|epsilon_{etau}|sim0.2$. We then compare the results from long-baseline data to constraints from IceCube and COHERENT.
We consider the MSSM with see-saw mechanism of neutrino mass generation and soft SUSY breaking with flavour-universal boundary conditions at the GUT scale, in which the lepton flavour violating (LFV) decays muto e + gamma, tauto mu + gamma, etc.,are predicted with rates that can be within the reach of present and planned experiments. These predictions depend critically on the matrix of neutrino Yukawa couplings bf{Y_{ u}} which can be expressed in terms of the light and heavy right-handed (RH) neutrino masses, neutrino mixing matrix U_{PMNS}, and an orthogonal matrix bf{R}. We investigate the effects of Majorana CP-violation phases in U_{PMNS}, and of the RG running of light neutrino masses and mixing angles from M_Z to the RH Majorana neutrino mass scale M_R, on the predictions for the rates of LFV decays muto e + gamma, tau to mu + gamma and tauto e + gamma. Results for neutrino mass spectrum with normal hierarchy, values of the lightest u-mass in the range 0 leq m_1 leq 0.30 eV, and quasi-degenerate heavy RH Majorana neutrinos in the cases of bf{R} = bf{1} and complex matrix bf{R} are presented. We find that the effects of the Majorana CP-violation phases and of the RG evolution of neutrino mixing parameters can change by few orders of magnitude the predicted rates of the LFV decays mu to e + gamma and tau to e + gamma. The impact of these effects on the tau to mu + gamma decay rate is typically smaller and only possible for m_1 > 0.10 eV. If the RG running effects are negligible, in a large region of soft SUSY breaking parameter space the ratio of the branching ratios of the mu to e + gamma and tau to e + gamma (tau to mu + gamma) decays is entirely determined in the case of bf{R} cong bf{1} by the values of the neutrino mixing parameters at M_Z.
We show that a source-to-detector distance of 2540 km offers multiple advantages for a low energy neutrino factory with a detector that can identify muon charge. At this baseline, for any neutrino hierarchy, the wrong-sign muon signal is almost independent of CP violation and $theta_{13}$ in certain energy ranges. This reduces the uncertainties due to these parameters and allows the identification of the hierarchy in a clean way. In addition, part of the muon spectrum is also sensitive to the CP violating phase and $theta_{13}$, so that the same setup can be used to probe these parameters as well.
The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE will resolve the neutrino mass hierarchy to a precision of 5$sigma$, for all $delta_{mathrm{CP}}$ values, after 2 years of running with the nominal detector design and beam configuration. It has the potential to observe charge-parity violation in the neutrino sector to a precision of 3$sigma$ (5$sigma$) after an exposure of 5 (10) years, for 50% of all $delta_{mathrm{CP}}$ values. It will also make precise measurements of other parameters governing long-baseline neutrino oscillation, and after an exposure of 15 years will achieve a similar sensitivity to $sin^{2} 2theta_{13}$ to current reactor experiments.
We perform realistic simulations of the current and future long baseline experiments such as T2K, NO$ u$A, DUNE and T2HK in order to determine their ultimate potential in probing neutrino oscillation parameters. We quantify the potential of these experiments to underpin the octant of the atmospheric angle $theta_{23}$ as well as the value and sign of the CP phase $delta_{CP}$.
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