Related papers: When $\tan \beta$ meets all the mixing angles
In the context of the radiative electroweak symmetry breaking scenario, we investigate the implications of a heavy top quark mass, close to its infrared fixed point, on the low energy parameters of the minimal supersymmetric standard model.…
We present a new (supersymmetric) framework for obtaining an excellent description of quark, charged lepton and neutrino masses and mixings from a Delta(6n^2) family symmetry with multiplet assignments consistent with an underlying SO(10)…
If a family symmetry exists for the quarks and leptons, the Higgs sector is expected to be enlarged to be able to support the transformation properties of this symmetry. There are however three possible generic ways (at tree level) of…
We consider a minimal condition that predicts the 1-3 lepton mixing angle $\theta_{13} \simeq \theta_{\rm C}/\sqrt{2}$ with $\theta_{\rm C}$ the Cabibbo angle, and give the improved prediction of $\theta_{13}$. In the case of normal mass…
We catalogue and study three-Higgs-doublet models in terms of all possible allowed symmetries (continuous and discrete, Abelian and non-Abelian), where such symmetries may be identified as flavour symmetries of quarks and leptons. We…
A scenario is presented where the $s$, $c$, and $b$ quark fusion Higgs production cross sections are enhanced with respect to those of the Standard Model. In particular the $c$ quark fusion production is very important and can account for a…
We present a model for lepton masses and mixing angles using the deconstruction setup, based on a non-Abelian flavor symmetry which is a split extension of the Klein group. The symmetries enforce an approximately maximal atmospheric mixing…
We investigate the renormalization group evolution of masses and mixing angles of Majorana neutrinos under the `High Scale Mixing Unification' hypothesis. Assuming the unification of quark-lepton mixing angles at a high scale, we show that…
While a chiral fourth generation of quarks is almost ruled out from the data on Higgs boson production and decay at the Large Hadron Collider, vector-like quarks are still a feasible option to extend the fermionic sector of the Standard…
We discuss a class of left-right symmetric theories with a universal seesaw mechanism for fermion masses and mixing and the implications for neutrinoless double beta ($0\nu\beta\beta$) decay where neutrino masses are governed by natural…
We consider constraints from flavor physics on two-Higgs-doublet models (2HDM) with general, flavor-diagonal, Yukawa couplings. Analyzing the charged Higgs contribution to different observables, we find that $b\to s\gamma$ transitions and…
The conjecture that some unknown symmetry is responsible for keeping the Higgs boson light at 125 GeV does not hold for the Standard Model, where the coefficient of the quadratic divergence of Higgs boson self-energy is far from zero. We…
We construct a supersymmetric model with the flavor symmetry D14 in which the CKM matrix element |V_{ud}| can take the value |V_{ud}| =cos (pi/14) = 0.97493 implying that the Cabibbo angle theta_C is sin (theta_C) = |V_{us}| = sin (pi/14) =…
Quarks, leptons and heavy vector bosons are suggested to be composed of stable spin-1/2 preons, existing in three flavours, combined according to simple rules. Straightforward consequences of an SU(3) preon-flavour symmetry are the…
When the Higgs doublets in the 3HDM transform as a flavor triplet of the $A_4$ group, the lepton mass matrices accommodate the experimental neutrino mixing angles at arbitrary precision while maintaining the correct mass ordering of the…
The complementarity between the quark and lepton mixing matrices is shown to provide a robust prediction for the neutrino mixing angle $\theta_{13}^{PMNS}$. We obtain this prediction by first showing that the matrix $V_M$, product of the…
We discuss an extension of the minimal Higgs triplet model with a classically conformal invariance and with a gauged $U(1)_{B-L}$ symmetry. In our scenario, tiny masses of neutrinos are generated by a hybrid contribution from the type-I and…
The discrete symmetry D_12 at the electroweak scale is used to fix the quark and lepton mixing angles. At the leading order, the Cabbibo angle theta_C is 15^o, and the PMNS matrix is of a bi-dodeca-mixing form giving the Solar-neutrino…
We study the process gg -> b bbar H+ H- at large tan(beta), where it represents the dominant production mode of charged Higgs boson pairs in a Type II 2-Higgs Doublet Model, including the Minimal Supersymmetric Standard Model. The ability…
We construct a three-Higgs doublet model with a flavour non-universal ${\rm U}(1)\times \mathbb{Z}_2$ symmetry. That symmetry induces suppressed flavour-changing interactions mediated by neutral scalars. New scalars with masses below the…