Neutrino Mass Spectrum: Present Indication and Future Prospect

The fact that neutrinos are massive has been the most crucial evidence of physics beyond the Standard Model of elementary particles. To date, we still do not know how neutrinos get mass and why their mass is much smaller than that of their charged fermion cousins. The precise determination of the neutrino mass spectrum has become one of the central tasks of neutrino physics, providing critical input for understanding the nature of neutrino mass and extending our model. The present landscape of the neutrino mass spectrum is reviewed and explored in this article using data from the neutrino oscillation, cosmology, and beta decay. In addition, we discuss the possibility of relevant programs elucidating the neutrino mass spectrum in the coming decades.

Generating Majorana neutrino masses with loops

We give a review on neutrino models in which Majorana neutrino masses are generated radiatively through loop diagrams. In particular, we concentrate on the two-loop models which contain extra doubly charged singlet [Formula: see text] and triplet [Formula: see text] scalars beyond the Standard Model so that the new Yukawa [Formula: see text] and effective [Formula: see text] couplings can be induced. In these two-loop models, we find that the neutrino mass spectrum is a normal hierarchy and the rate of the neutrinoless double beta decay [Formula: see text] can be large as it is dominated by the short-distance tree contribution. In addition, by using the neutrino oscillation data and comparing with the global fitting result in the literature, we find a unique neutrino mass matrix and predict the Dirac and two Majorana CP phases to be [Formula: see text], [Formula: see text] and [Formula: see text] with [Formula: see text], respectively.

Re-examination of Two Zero Texture of Neutrino Mass Matrix After Neutrino-2012

We re-study the seven neutrino mass matrices with two independent vanishing entries under the latest results of neutrino oscillation experiments after the neutrino - 2012 conference. It is shown that the pattern B 1 could be excluded since this pattern realizes very small value of mixing angle theta13. The remain six textures satisfy the current experimental data. We also find that all seven textures of neutrino mass matrix possess the normal hierarchy of neutrino mass spectrum.

NEUTRINO MIXING IN THE μνSSM

Recently, several reactor oscillation experiments have successively measured a nonzero value for the neutrino mixing angle θ13, which is greater than five standard deviations. Within framework of the μ from ν Supersymmetric Standard Model (μνSSM), three tiny neutrino masses are generated at the tree level through TeV scale seesaw mechanism. In this work, we analyze the neutrino masses and mixing in the μνSSM with a "top-down" method, assuming neutrino mass spectrum with normal ordering or inverted ordering.