Related papers: Consequences of a U(2) Flavour Symmetry
In a generic supersymmetric extension of the Standard Model, whether unified or not, a simple and well motivated U(2) symmetry, acting on the lightest two generations, completely solves the flavour changing problem and necessarily leads to…
A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the second and the third family, in agrement with observation. Introducing the mixing between the first and the second family, one finds an interesting…
We study the impact of an additional $U(1)'$ gauge symmetry with flavour-dependent charges for quarks and leptons on the LHC flavour anomalies observed in $B \to K^* \mu^+\mu^-$, $R(K) = B \to K \mu^+\mu^-/B \to K e^+e^-$, and $h \to…
We propose a simple $U(2)$ model of flavor compatible with an $SU(5)$ GUT structure. All hierarchies in fermion masses and mixings arise from powers of two small parameters that control the $U(2)$ breaking. In contrast to previous $U(2)$…
Models involving a U(2) flavor symmetry, or any of a number of its non-Abelian discrete subgroups, can explain the observed hierarchy of charged fermion masses and CKM angles. It is known that a large neutrino mixing angle connecting second…
Flavor-changing and CP-violating interactions of Z' to fermions are generally present in models with extra U(1) gauge symmetry that are string-inspired or related to broken gauged family symmetry. We study the consequences of such couplings…
We discuss the characteristic low energy phenomenological implications of an SU(5) Supersymmetric Grand Unified Theory (SUSY GUT) whose flavour structure is controlled by the family symmetry S4 x U(1), which provides a good description of…
This dissertation investigates the flavor mixing effects in supersymmetric models on electroweak precision observables, Higgs boson mass predictions, B-physics observables, quark flavor violating Higgs decays, lepton flavor violating…
We present a model of fermion masses based on a minimal, non-Abelian discrete symmetry that reproduces the Yukawa matrices usually associated with U(2) theories of flavor. Mass and mixing angle relations that follow from the simple form of…
Present situation in the flavour mixing of quarks and leptons is briefly reviewed and a new approach called the Minimal Flavour Mixing (MFM) is considered in detail. According to MFM the whole of the flavour mixing is basically determined…
Rather than sticking to the full $U(3)^3$ approximate symmetry normally invoked in Minimal Flavour Violation, we analyze the consequences on the current flavour data of a suitably broken $U(2)^3$ symmetry acting on the first two generations…
The origin of flavour and CP violation is among the most important open questions in particle physics. Imminent results from the LHC as well as planned dedicated flavour physics experiments might help to shed light on this puzzle. This talk…
We present an effective flavor model for the radiative generation of fermion masses and mixings based on a SU(5)xU(2) symmetry. We assume that the original source of flavor breaking resides in the supersymmetry breaking sector. Flavor…
We address the flavour problem by incorporating the hypothesis of universal strength of Yukawa couplings in the framework of a 5D GUT model compactified on an $S^1/(Z_2 \times Z_2^{\prime})$ orbifold. We show that a quantitatively…
In order to explain the fermions masses and mixing parameters appearing in the lepton sector of the Standard Model, one proposes the extension of its symmetry. A discrete, non-abelian subgroup of $U(3)$ is added to the gauge group…
Without assuming any specific flavor symmetry and/or any specific mass matrix forms, it is demonstrated that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot obtain the CKM quark mixing matrix $V$ and…
We study the extension of the Minimal Flavour Violation (MFV) hypothesis to the MSSM without R-parity. The novelty of our approach lies in the observation that supersymmetry enhances the global symmetry of the kinetic term and in the fact…
We argue that flavour mixing, both in the quark and charged lepton sector, is basically determined by the lightest family mass generation mechanism. So, in the chiral symmetry limit when the up and down quark masses vanish, all the quark…
We review and compare theoretically and phenomenologically a number of possible family symmetries, which when combined with unification, could be important in explaining quark, lepton and neutrino masses and mixings, providing new results…
We study two-site deconstructions of the $SU(2)_L$ gauge group factor of the SM. Models based on this approach can explain the hierarchies of the quark masses and CKM mixing between third and light families if these fields are localised on…