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We propose a model based on the $SU(5)$ grand unification with an extra $Z_{2}\otimes Z_{2}^{\prime}\otimes Z_{2}^{\prime \prime}\otimes Z_{4}\otimes Z_{12}$ flavor symmetry, which successfully describes the observed SM fermion mass and…

High Energy Physics - Phenomenology · Physics 2014-11-13 A. E. Cárcamo Hernández , Sergey Kovalenko , Iván Schmidt

Diverse mass and mixing patterns between the quarks and leptons makes it challenging to construct a simple grand unified theory of flavor. We show that SO(10) SUSY GUTs with type II seesaw mechanism giving neutrino masses provide a natural…

High Energy Physics - Phenomenology · Physics 2014-11-20 Bhaskar Dutta , Yukihiro Mimura , R. N. Mohapatra

We employ a bottom-up and model-independent technique to search for non-Abelian discrete flavour symmetries capable of predicting viable CKM and PMNS matrices alongside of special patterns of leptoquark couplings. In particular, we analyze…

High Energy Physics - Phenomenology · Physics 2020-02-19 Jordan Bernigaud , Ivo de Medeiros Varzielas , Jim Talbert

We consider extension of the standard model $SU(2)_l \times SU(2)_h \times U(1)$ where the first two families of quarks and leptons transform according to the $SU(2)_l$ group and the third family according to the $SU(2)_h$ group. In this…

High Energy Physics - Phenomenology · Physics 2010-04-06 Cheng-Wei Chiang , N. G. Deshpande , Xiao-Gang He , J. Jiang

We construct an extension of the Standard Model with a scalar leptoquark $\phi \sim (3,1,-\tfrac13)$ and the discrete flavour symmetry $G_f=D_{17}\times Z_{17}$ to explain anomalies observed in charged-current semi-leptonic $B$ meson decays…

High Energy Physics - Phenomenology · Physics 2023-10-23 Innes Bigaran , Tobias Felkl , Claudia Hagedorn , Michael A. Schmidt

The most statistically significant hints for new physics in the flavor sector are discrepancies between theory and experiment in $B$ decays to lepton pairs ($b\to s\ell^+\ell^-$) and a deficit in $1^{\rm st}$ row CKM unitarity (the Cabibbo…

High Energy Physics - Phenomenology · Physics 2021-02-03 Bernat Capdevila , Andreas Crivellin , Claudio Andrea Manzari , Marc Montull

New neutral heavy gauge bosons ($Z^\prime$) are predicted within many extensions of the Standard Model. While in case they couple to quarks the LHC bounds are very stringent, leptophilic $Z^\prime$ bosons (even with sizable couplings) can…

High Energy Physics - Phenomenology · Physics 2021-06-30 Andrzej J. Buras , Andreas Crivellin , Fiona Kirk , Claudio Andrea Manzari , Marc Montull

We analyse the recent hints of Lepton Flavor Universality violations in semi-leptonic $B$ decays within a general EFT based on a $U(2)^n$ flavor symmetry acting on the light generations of SM fermions. We analyse in particular the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Marzia Bordone , Gino Isidori , Sokratis Trifinopoulos

The quark and charged lepton masses and the angles and phase of the CKM mixing matrix are nicely reproduced in a model which assumes SU(3)xSU(3) flavour symmetry broken by the v.e.v.'s of fields in its bi-fundamental representation. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. Masina , C. A. Savoy

In the framework of a complete vector-like and universal gauged SU(3)_F family symmetry, we report a global region in the parameter space where this approach can account for a realistic spectrum of quark masses and mixing in a 4 x 4…

High Energy Physics - Phenomenology · Physics 2016-12-23 Albino Hernandez-Galeana

The Standard Model (SM) is lepton flavor universal, and the recent measurements of lepton flavor universality in $B \to (K,K^*)\ell^{+}\ell^{-}$, for $\ell = \mu, \; e$, decays now lie close to the SM predictions. However, this is not the…

High Energy Physics - Phenomenology · Physics 2026-03-13 Ishtiaq Ahmed , Saba Shafaq , M. Jamil Aslam , Saadi Ishaq

We propose a variant of the Pati-Salam model, with gauge group $SU(4)_C\times SU(2)_L\times U(1)_{Y'}$, in which the chiral left-handed quarks and leptons are unified into a $\underline{4}$ of $SU(4)_C$, while the right-handed quarks and…

High Energy Physics - Phenomenology · Physics 2019-01-30 Shyam Balaji , Robert Foot , Michael A. Schmidt

Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide…

High Energy Physics - Phenomenology · Physics 2018-12-18 Bradley L. Rachlin , Thomas W. Kephart

The coupling of the electroweak gauge bosons of the Standard Model (SM) to leptons is flavour universal. Extensions of the SM do not necessarily have this property. Rare decays of heavy flavour are suppressed in the SM and new particles may…

High Energy Physics - Experiment · Physics 2021-03-02 Carla Marin Benito

Leptoquarks are prime candidates for explaining the intriguing hints for lepton flavour universality violation. In particular, the $SU(2)_L$ doublet of scalar leptoquarks $S_2$ is capable of providing an explanation for the tensions between…

High Energy Physics - Phenomenology · Physics 2022-07-05 Andreas Crivellin , Benjamin Fuks , Luc Schnell

We perform a global analysis of a vector-like extension of the Standard Model, which also features additional doublet and singlet scalars. The usual Yukawa interactions are forbidden in this setup by an extra U(1) global symmetry and the…

High Energy Physics - Phenomenology · Physics 2024-07-22 A. E. Cárcamo Hernández , Kamila Kowalska , Huchan Lee , Daniele Rizzo

The concept of lepton flavour universality (LFU), according to which the three lepton families are equivalent except for their masses, is a cornerstone prediction of the Standard Model (SM). LFU can be violated in models beyond the SM by…

High Energy Physics - Experiment · Physics 2019-05-22 Elena Graverini

We study the generic features of minimal gauge extensions of the Standard Model in view of recent hints of lepton-flavor non-universality in semi-leptonic $b \to s \ell^+ \ell^-$ and $b \to c \ell \nu$ decays. We classify the possible…

High Energy Physics - Phenomenology · Physics 2016-07-08 Sofiane M. Boucenna , Alejandro Celis , Javier Fuentes-Martin , Avelino Vicente , Javier Virto

Assuming confirmation of the anomalies in semi-leptonic $B$-decays, their explanation in terms of the exchange of a massive vector leptoquark field, $U_\mu^a$, of charge 2/3, appears to require the inclusion of $U_\mu^a$ in the vector…

High Energy Physics - Phenomenology · Physics 2023-01-18 Riccardo Barbieri , Claudia Cornella , Gino Isidori

Driven by the recent experimental hints of lepton-flavor-universality violation in the bottom-quark sector, we consider a simple extension of the Standard Model (SM) with an additional vector leptoquark $V_{\rm LQ}({\bf 3},{\bf 1},2/3)$ and…

High Energy Physics - Phenomenology · Physics 2020-11-16 P. S. Bhupal Dev , Rukmani Mohanta , Sudhanwa Patra , Suchismita Sahoo