scholarly journals Nonzero |U e3| from charged lepton corrections and the atmospheric neutrino mixing angle

2013 ◽  
Vol 2013 (5) ◽  
Author(s):  
David Marzocca ◽  
S. T. Petcov ◽  
Andrea Romanino ◽  
M. C. Sevilla
2012 ◽  
Vol 27 (31) ◽  
pp. 1250180 ◽  
Author(s):  
TERUYUKI KITABAYASHI

The tribimaximal mixing describes the observed solar and atmospheric neutrino mixings; however, it predicts vanishing reactor neutrino mixing angle, which is inconsistent with the observed data. We show a way of minimally modifying the tribimaximal mixing by including charged lepton contributions.


2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Madan Singh

We have studied that the implication of a large value of the effective Majorana neutrino mass in case of neutrino mass matrices has either two equal elements and one zero element (popularly known as hybrid texture) or two equal cofactors and one zero minor (popularly known as inverse hybrid texture) in the flavor basis. In each of these cases, four out of sixty phenomenologically possible patterns predict near maximal atmospheric neutrino mixing angle in the limit of large effective Majorana neutrino mass. This feature remains irrespective of the experimental data on solar and reactor mixing angles. In addition, we have also performed the comparative study of all the viable cases of hybrid and inverse hybrid textures at 3σ CL.


2013 ◽  
Vol 28 (31) ◽  
pp. 1350131 ◽  
Author(s):  
SRINU GOLLU ◽  
K. N. DEEPTHI ◽  
R. MOHANTA

The recent results from Daya Bay and RENO reactor neutrino experiments have firmly established that the smallest reactor mixing angle θ13 is nonvanishing at the 5 σ level, with a relatively large value, i.e. θ13 ≈ 9°. Using the fact that the neutrino mixing matrix can be represented as [Formula: see text], where Ul and Uν result from the diagonalization of the charged lepton and neutrino mass matrices and Pν is a diagonal matrix containing the Majorana phases and assuming the tri-bimaximal (TBM) form for Uν, we investigate the possibility of accounting for the large reactor mixing angle due to the corrections of the charged lepton mixing matrix. The form of Ul is assumed to be that of CKM mixing matrix of the quark sector. We find that with this modification it is possible to accommodate the large observed reactor mixing angle θ13. We also study the implications of such corrections on the other phenomenological observables.


1996 ◽  
Vol 11 (36) ◽  
pp. 2849-2859 ◽  
Author(s):  
YOSHIO KOIDE

On the basis of a seesaw-type mass matrix model for quarks and leptons, [Formula: see text] where mL∝mR are universal for f=u, d, v and e (up-quark, downquark, neutrino and charged lepton sectors respectively), and MF has a form [(unit matrix)+(democratic-type matrix)], neutrino masses and mixings are investigated. We try to understand a large vµ−vτ mixing, i.e. sin2 2θ23~1, with mv1 ≪ mv2~mv3, which has been suggested by the atmospheric neutrino data.


2011 ◽  
Vol 26 (02) ◽  
pp. 179-189
Author(s):  
◽  
TINGJUN YANG

The MINOS experiment uses the NuMI νμ beam to make precise measurements of neutrino flavor oscillations in the "atmospheric" neutrino sector. MINOS can also probe the yet-unknown neutrino mixing angle θ13 by searching for a νe appearance signal in the νμ beam. This paper reviews the techniques developed for the first νe appearance analysis in MINOS.


2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
D. V. Ahluwalia

In view of the new data from the Daya Bay and RENO collaborations, King has presented a very natural deformation of tri-bimaximal mixing. Here, we show that L/E flatness of the e-like event ratio in the atmospheric neutrino data, when coupled with King's observation that the smallest neutrino mixing angle, , seems to be related to the largest quark mixing angle (the Cabibbo angle ), leading to a CP violating tri-bimaximal-Cabibbo mixing. King's tri-bimaximal-Cabibbo mixing follows as a leading order approximation from our result.


2006 ◽  
Vol 21 (13) ◽  
pp. 1067-1073 ◽  
Author(s):  
AMBAR GHOSAL ◽  
DEBASISH MAJUMDAR

We demonstrate that "Bimaximal + Democratic" type neutrino mass matrix can accommodate the deviation of θ⊙ from its maximal value along with the other present-day neutrino experimental results, namely, atmospheric, CHOOZ, neutrinoless double beta decay (ββ0ν) and result obtained from WMAP experiment. We define a function χp in terms of solar and atmospheric neutrino mass squared differences and solar neutrino mixing angle (obtained from different experiments and our proposed texture). The masses and mixing angles are expressed in terms of three parameters in our proposed texture. The allowed region of the texture parameters is obtained through minimization of the above function. The proposed texture crucially depends on the value of the experimental results of ββ0ν experiment among all other above-mentioned experiments. If, in future, ββ0ν experiments, namely, MOON, EXO, GENIUS shift the lower bound on 〈mee〉 at the higher side by one order, the present texture will be ruled out.


2014 ◽  
Vol 29 (18) ◽  
pp. 1450095 ◽  
Author(s):  
P. F. Harrison ◽  
R. Krishnan ◽  
W. G. Scott

We present a model of neutrino mixing based on the flavor group Δ(27) in order to account for the observation of a nonzero reactor mixing angle (θ13). The model provides a common flavor structure for the charged-lepton and the neutrino sectors, giving their mass matrices a "circulant-plus-diagonal" form. Mass matrices of this form readily lead to mixing patterns with realistic deviations from tribimaximal mixing, including nonzero θ13. With the parameters constrained by existing measurements, our model predicts an inverted neutrino mass hierarchy. We obtain two distinct sets of solutions in which the atmospheric mixing angle lies in the first and the second octants. The first (second) octant solution predicts the lightest neutrino mass, m3~29 meV (m3~65 meV ) and the CP phase, [Formula: see text], offering the possibility of large observable CP violating effects in future experiments.


2003 ◽  
Vol 18 (20) ◽  
pp. 1355-1365 ◽  
Author(s):  
Bipin R. Desai ◽  
Alexander R. Vaucher ◽  
D. P. Roy

Out of the 15 3 × 3 neutrino mass matrices with two texture zeros, seven are compatible with the neutrino oscillation data. While two of them correspond to hierarchical neutrino masses and 1 to an inverted hierarchy, the remaining four correspond to degenerate masses. Moreover only the first three of the seven mass matrices are compatible with the maximal mixing angle of atmospheric neutrino and hence favored by data. We give compact expressions for mass matrices in terms of mass eigenvalues and study phenomenological implications for the seven cases. Similarity of the textures of the neutrino, charged-lepton mass matrices with those of quark mass matrices is also discussed.


2007 ◽  
Vol 16 (05) ◽  
pp. 1361-1372 ◽  
Author(s):  
ZHI-ZHONG XING

I argue that the observed flavor structures of leptons and quarks might imply the existence of certain flavor symmetries. The latter should be a good starting point to build realistic models towards deeper understanding of the fermion mass spectra and flavor mixing patterns. The μ-τ permutation symmetry serves for such an example to interpret the almost maximal atmospheric neutrino mixing angle (θ23 ~ 45°) and the strongly suppressed CHOOZ neutrino mixing angle (θ13 < 10°). In this talk I like to highlight a new kind of flavor symmetry, the Friedberg–Lee symmetry, for the effective Majorana neutrino mass operator. Luo and I have shown that this symmetry can be broken in an oblique way, such that the lightest neutrino remains massless but an experimentally-favored neutrino mixing pattern is achievable. We get a novel prediction for θ13 in the CP-conserving case: sin θ13 = tan θ12|(1 - tan θ23)/(1 + tan θ23)|. Our scenario can simply be generalized to accommodate CP violation and be combined with the seesaw mechanism. Finally I stress the importance of probing possible effects of μ-τ symmetry breaking either in terrestrial neutrino oscillation experiments or with ultrahigh-energy cosmic neutrino telescopes.


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