English
Related papers

Related papers: Effective alignments and the landscape of $S_4$ fl…

200 papers

Flavour models typically rely on flavons - scalars that break the family symmetry by acquiring vacuum expectation values in specific directions. We develop the idea of effective alignments, i.e.\ cases where the contractions of multiple…

High Energy Physics - Phenomenology · Physics 2018-07-11 Ivo de Medeiros Varzielas , Thomas Neder , Ye-Ling Zhou

We study lepton flavor models with the $S_4$ flavor symmetry. We construct simple models with smaller numbers of flavon fields and free parameters, such that we have predictions among lepton masses and mixing angles. The model with a $S_4$…

High Energy Physics - Phenomenology · Physics 2015-05-28 Hajime Ishimori , Tatsuo Kobayashi

We analyse how $U(3)^5$ and $U(2)^5$ flavour symmetries act on the Standard Model Effective Field Theory, providing an organising principle to classify the large number of dimension-six operators involving fermion fields. A detailed…

High Energy Physics - Phenomenology · Physics 2025-04-23 Darius A. Faroughy , Gino Isidori , Felix Wilsch , Kei Yamamoto

Flavor symmetry has been widely studied for figuring out the masses and mixing angles of standard-model fermions. In this paper we present a framework for handling flavor symmetry breaking where the symmetry breaking is triggered by…

High Energy Physics - Phenomenology · Physics 2008-12-30 Tatsuo Kobayashi , Yuji Omura , Koichi Yoshioka

In models with discrete flavour symmetries, flavons are critical to realise specific flavour structures. Leptonic flavour mixing originates from the misalignment of flavon vacuum expectation values which respect different residual…

High Energy Physics - Phenomenology · Physics 2016-06-14 Silvia Pascoli , Ye-Ling Zhou

We consider a class of discrete flavour symmetries for leptons based on the group S(3) and A(4) with an hybrid breaking pattern. The aim is to construct models in which the same flavon fields producing the mixing pattern are also…

High Energy Physics - Phenomenology · Physics 2010-11-11 Yin Lin

We study the flavor structure of the lepton and baryon number--conserving dimension-6 operators in the Standard Model effective field theory (SMEFT). Building on the work of [1], we define several well-motivated flavor symmetries and…

High Energy Physics - Phenomenology · Physics 2023-05-26 Admir Greljo , Ajdin Palavrić , Anders Eller Thomsen

We develop a general formalism for multiple moduli and their associated modular symmetries. We apply this formalism to an example based on three moduli with finite modular symmetries $S_4^A$, $S_4^B$ and $S_4^C$, associated with two…

High Energy Physics - Phenomenology · Physics 2020-04-01 Ivo de Medeiros Varzielas , Stephen F. King , Ye-Ling Zhou

Discrete flavour symmetries have been proven successful in explaining the leptonic flavour structure. To account for the observed mixing pattern, the flavour symmetry has to be broken to different subgroups in the charged and neutral lepton…

High Energy Physics - Phenomenology · Physics 2012-01-31 Martin Holthausen , Michael A. Schmidt

We show how two principles - strong coupling and discrete symmetry - can work together to generate the flavour structure of the Standard Model. We propose that in the UV the full theory has a discrete flavour symmetry, typically only…

High Energy Physics - Phenomenology · Physics 2015-03-17 Steven Abel , James Barnard

We present a supersymmetric see-saw $S_4$ model giving rise to the most general neutrino mass matrix compatible with Tri-Bimaximal mixing. We adopt the $S_4\times Z_5$ flavour symmetry, broken by suitable vacuum expectation values of a…

High Energy Physics - Phenomenology · Physics 2015-05-14 Davide Meloni

We present a supersymmetric model of quark and lepton based on $S_4\times Z_3\times Z_4$ flavor symmetry. The $S_4$ symmetry is broken down to Klein four and $Z_3$ subgroups in the neutrino and the charged lepton sectors respectively.…

High Energy Physics - Phenomenology · Physics 2009-12-04 Gui-Jun Ding

We present a framework for lepton flavour models such that the first column of the lepton mixing matrix is (2,-1,-1)/sqrt(6). We show that the flavour symmetry group adequate for this purpose is S4. Our models are based on a vacuum…

High Energy Physics - Phenomenology · Physics 2015-06-12 Ivo de Medeiros Varzielas , Luís Lavoura

Effective Flavour Models do not address questions related to the nature of the fundamental renormalisable theory at high energies. We study the ultraviolet completion of Flavour Models, which in general has the advantage of improving the…

High Energy Physics - Phenomenology · Physics 2011-03-18 Ivo de Medeiros Varzielas , Luca Merlo

In flavor models the vacuum alignment of flavons is typically achieved via the $F$-terms of certain fields in the supersymmetric limit. We propose a method for preserving such alignments, up to a rescaling of the vacuum expectation values,…

High Energy Physics - Phenomenology · Physics 2023-12-13 Claudia Hagedorn , M. L. López-Ibáñez , M. Jay Pérez , Moinul Hossain Rahat , Oscar Vives

In leptonic flavour models with discrete flavour symmetries, couplings between flavons and leptons can result in special flavour structures after they gain vacuum expectation values. At the same time, they can also contribute to the other…

High Energy Physics - Phenomenology · Physics 2016-10-28 Silvia Pascoli , Ye-Ling Zhou

Eclectic flavor groups arising from string compactifications combine the power of modular and traditional flavor symmetries to address the flavor puzzle. This top-down scheme determines the representations and modular weights of all matter…

High Energy Physics - Phenomenology · Physics 2022-10-03 Alexander Baur , Hans Peter Nilles , Saul Ramos-Sanchez , Andreas Trautner , Patrick K. S. Vaudrevange

We construct lepton flavour models based on two $A_4$ modular symmetries. The two $A_4$ are broken by a bi-triplet field to the diagonal $A_4$ subgroup, resulting in an effective modular $A_4$ flavour symmetry with two moduli. We employ…

High Energy Physics - Phenomenology · Physics 2022-06-15 Ivo de Medeiros Varzielas , João Lourenço

The flavour puzzle is an open problem both in the Standard Model and in its possible supersymmetric or grand unified extensions. In this thesis, we discuss possible explanations of the origin of fermion mass hierarchies and mixings by the…

High Energy Physics - Phenomenology · Physics 2010-12-16 Luca Merlo

We produce five flavour models for the lepton sector. All five models fit perfectly well---at the one-sigma level---the existing data on the neutrino mass-squared differences and on the lepton mixing angles. The models are based on the…

High Energy Physics - Phenomenology · Physics 2015-06-15 P. M. Ferreira , L. Lavoura , P. O. Ludl
‹ Prev 1 2 3 10 Next ›