Sterile neutrinos in the 3+s scenario and solar data

The flatness of the SuperKamiokande neutrino electron scattering spectrum and the apparent downturn of the charged current spectrum in the SNO data which the Large Mixing Angle solution (LMA) to the solar neutrino problem fails to predict are analysed in the context of an extension to the standard electroweak model with light sterile neutrinos. It is found that a sterile neutrino which is quasi degenerate with the active ones with $\Delta m^2_{41}=10^{-5}eV^2$ and mixing $sin\theta_{14}=0.04$ provides a suitable improvement to the LMA data fits.

EFFECTS OF BSMS ON θ23 DETERMINATION

Determination of the θ23 octant in long baseline neutrino experiments within and beyond the standard model

The recent data indicate that the neutrino mixing angle $\theta_{23}$ deviates from the maximal-mixing value of 45$^\circ$, showing two nearly degenerate solutions, one in the lower octant (LO) ($\theta_{23}45^\circ$). We investigate, using numerical simulations, the prospects for determining the octant of $\theta_{23}$ in the future long baseline oscillation experiments. We present our results as contour plots on the ($\theta_{23}-45^\circ$, $\delta$)--plane, where $\delta$ is the $CP$ phase, showing the true values of $\theta_{23}$ for which the octant can be experimentally determined at 3$\,\sigma$, 2$\,\sigma$ and 1$\,\sigma$ confidence level. In particular, we study the impact of the p…

Determination of the $\theta_{23}$ octant in LBNO

According to the recent results of the neutrino oscillation experiment MINOS, the neutrino mixing angle $\theta_{23}$ may not be maximal ($45^{\circ}$). Two nearly degenerate solutions are possible, one in the lower octant (LO) where $\theta_{23}45^{\circ}$. Long baseline experiments measuring the $\nu_{\mu}\rightarrow\nu_{e}$ are capable of resolving this degeneracy. In this work we study the potential of the planned European LBNO experiment to distinguish between the LO and HO solutions.

Determination of the θ23 octant in long baseline neutrino experiments within and beyond the standard model

The recent data indicate that the neutrino mixing angle θ 23 deviates from the maximal-mixing value of 45°, showing two nearly degenerate solutions, one in the lower octant (LO) ( θ 23 4 5 ° ). We investigate, using numerical simulations, the prospects for determining the octant of θ 23 in the future long baseline oscillation experiments. We present our results as contour plots on the ( θ 23 − 4 5 ° , δ )–plane, where δ is the C P phase, showing the true values of θ 23 for which the octant can be experimentally determined at 3 σ , 2 σ and 1 σ confidence level. In particular, we study the impact of the possible nonunitarity of neutrino mixing on the experimental determination of θ 23 in thos…