相关论文: Neutrino Mixing by modifying the Yukawa coupling s…
The pattern of lepton mixing can emerge from breaking a flavor symmetry in different ways in the neutrino and charged lepton Yukawa sectors. In this framework, we derive the conditions imposed on the mixing matrix by the structure of…
We present a Two-Higgs-Doublet Model in which the structure of the quark Yukawa matrices is governed by three spurions breaking the flavour symmetries of the quark Yukawa sector. The model naturally suppresses flavour-changing neutral…
We study a possibility to explain neutrino masses and mixings based on supersymmetry. If we introduce a flavor diagonal but generation dependent extra U(1) gauge interaction at a TeV region, we can obtain masses and mixings of neutrinos…
In this paper we discuss a new way to derive neutrino mixing patterns, which originates from the idea proposed in a recent article by Hernandez and Smirnov. Its applications to various cases are discussed. We first present the complete set…
We study the case of $U^T_l$ presenting the exact bi-maximal mixing form with $U_\nu$ inducing the deviation from the bi-maximal mixing in the final form of the Pontecorvo-Maki-Nakagawa-Sakata neutrino mixing, $U_{PMNS}=U^T_l U_\nu$. We…
We analyze the stability of the electroweak vacuum in neutrino mass models containing right handed neutrinos or fermionic isotriplets. In addition to considering absolute stability, we place limits on the Yukawa couplings of new fermions…
We study parameters of an extension of the Standard Model. The neutrino sector is enlarged by one right-handed singlet field, allowing for the seesaw mechanism type-I, and the Higgs sector contains one additional doublet, which contributes…
It is pointed out that important contribution to neutrino masses and mixing can come from flavour violating slepton exchange. For low and intermediate $\tan\beta$ such effects can dominate over the usual tau Yukawa coupling effects included…
Assuming the same form of all mass matrices as motivated by quark-lepton symmetry, we discuss conditions under which bi-large mixing in the lepton sector can be obtained with a minimal amount of fine tuning requirements for possible models.…
At the occasion of his eighty fifth birthday, I wish to to recognize the crucial role that my advisor, Professor Ayalam Balachandran, played in enabling me to evolve from engineering to physics. So many years later, this student presents…
To address the issue of whether tri-bimaximal mixing (TBM) is a softly-broken hidden or an accidental symmetry, we adopt a model-independent analysis in which we perturb a neutrino mass matrix leading to TBM in the most general way but…
Nonzero masses for the active neutrinos - regardless of their nature or origin - arise only after electroweak symmetry breaking. We discuss the parameterization of neutrino couplings to a Higgs sector consisting of one SU(2)_L scalar…
We study neutrino masses and mixing in Supersymmetric Models without $R$ parity and with generic soft Supersymmetry breaking terms. Neutrinos acquire mass from various sources: tree level neutrino--neutralino mixing, loop effects and…
We analyze a scenario where the right-handed neutrinos make part of a strongly coupled conformal field theory and acquire an anomalous dimension \gamma<1 at a large scale \Lambda. Their Yukawa couplings to the Higgs become irrelevant at the…
CP violation, fermion masses and mixing angles including that of neutrinos are studied in an SUSY SO(10)$\times \Delta (48)\times$ U(1) model. The nonabelian SU(3) discrete family symmetry $\Delta(48)$ associated with a simple scheme of…
Symmetry-based ideas, such as the quark-lepton complementarity (QLC) principle and the tri-bimaximal mixing (TBM) scheme, have been proposed to explain the observed mixing pattern of neutrinos. We argue that such symmetry relations need to…
The observed neutrino mixing, having a near maximal atmospheric neutrino mixing angle and a large solar mixing angle, is close to tri-bi-maximal. We argue that this structure suggests a family symmetric origin in which the magnitude of the…
On account of the new neutrino oscillation data signalling a non-zero value for the smallest mixing angle ($\theta_z$), we present an explicit realization of the underlying U(1) symmetry characterizing the maximal atmospheric mixing angle…
We have studied how observables of the neutrino mixing matrix can link up with the ones in the quark sector. The deviation from the bi-maximal flavor mixing is parameterized using a 3 x 3 unitary matrix. The neutrino mixings are…
CP violation, fermion masses and mixing angles including that of neutrinos are studied in an SUSY SO(10)$\times \Delta (48)\times$ U(1) model with small $\tan \beta$. The family symmetry $\Delta(48)$ associated with a simple scheme of U(1)…