Fermion Texture and Sterile Neutrinos
Abstract
An explicit form of chargedlepton mass matrix, predicting m_{τ }= 1776.80 MeV from the experimental values of m_{e} and m_{μ }(in good agreement with the experimental figure m_{τ }=1777.05^{+0.29}_{0.26} MeV), is applied to three neutrinos ν _{e} , ν _{μ }, ν _{τ }in order to correlate tentatively their masses and mixing parameters. It is suggested that for neutrinos the diagonal elements of the mass matrix are small versus its offdiagonal elements. Under such a conjecture, the neutrino masses, lepton CabibboKobayashiMaskawa matrix and neutrino oscillation probabilities are calculated in the corresponding lowest perturbative order. Then, the nearly maximal mixing of ν _{μ }and ν _{τ }is predicted in consistency with the observed deficit of atmospheric ν _{μ }'s. However, the predicted deficit of solar ν _{e} 's is much too small to explain the observed effect, what suggests the existence of (at least) one sort, {ν _{s}^{(e)}} , of sterile neutrinos, whose mixing with ν _{e} would be responsible for the observed deficit. Perspectives for applying the same form of mass matrix to quarks are also outlined. Two independent predictions of V_{ub}/V_{cb} = 0.0753 ± 0.0032 and unitary angle γ ≃ 70 ° are deduced from the experimental values of V_{us} and V_{cb} (with the use of quark masses m_{s} , m_{c} and m_{b} ). In the last three Sections, the option of two sorts, {ν _{s}^{(e)}} and {ν _{s}^{(μ )} }, of sterile neutrinos is considered. They may dominate neutrino mixing, and even cause that two extra neutrino mass states (arising then) are agents of some tiny neutrino instability and related damping of ν _{e} and ν _{μ }oscillations. In Appendix, three conventional Majorana sterile neutrinos are discussed.
 Publication:

Acta Physica Polonica B
 Pub Date:
 September 1999
 arXiv:
 arXiv:hepph/9903209
 Bibcode:
 1999AcPPB..30.2631K
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 LaTeX, 40 pages