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Related papers: Flavor Constraints from Unitarity and Analyticity

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The $SU(2)_L\times U(1)_Y$ invariance of the Standard Model Effective Field Theory (SMEFT) predicts multiple restrictions in the space of Wilson coefficients of $U(1)_{em}$ invariant effective lagrangians such as the Low-energy Effective…

High Energy Physics - Phenomenology · Physics 2024-04-17 Siddhartha Karmakar , Amol Dighe , Rick S. Gupta

We determine the renormalization constants for flavor non-singlet fermion bilinear operators of M\"obius domain-wall fermions. The renormalization condition is imposed on the correlation functions in the coordinate space, such that the…

High Energy Physics - Lattice · Physics 2016-09-14 JLQCD collaboration , M. Tomii , G. Cossu , B. Fahy , H. Fukaya , S. Hashimoto , T. Kaneko , J. Noaki

Recent improved measurements of B decays probing the b->s flavour-changing neutral current have put strong constraints on flavour violation beyond the Standard Model. This talk reviews a model-independent analysis of these decays, which…

High Energy Physics - Phenomenology · Physics 2012-05-29 David M. Straub

Short-distance new physics at (or slightly) above the TeV scale should not excessively violate the approximate flavor symmetries of the SM in order to comply with stringent constraints from flavor-changing neutral currents. In this respect,…

High Energy Physics - Phenomenology · Physics 2023-05-17 Admir Greljo , Ajdin Palavrić

Addressing the ${(g-2)_\mu}$ anomaly and simultaneously being consistent with the tight bounds on ${\mu \to e \gamma}$ requires a precise alignment of the lepton dipole operator in flavor space. We investigate this alignment condition in…

High Energy Physics - Phenomenology · Physics 2022-01-24 Felix Wilsch

The effects of physics beyond the Standard Model may be parametrized by a set of higher-dimensional operators leading to an effective theory. The introduction of these operators makes the theory nonrenormalizable, and one may reasonably…

High Energy Physics - Phenomenology · Physics 2018-01-17 Swagata Ghosh , Rashidul Islam , Anirban Kundu

We consider the leading-order expression at weak-coupling for a single-site large-N gauge theory coupled to adjoint fermions. We study the case of overlap and wilson fermions. We extend the theory to real values of the number of fermion…

High Energy Physics - Lattice · Physics 2013-06-26 Robert Lohmayer , Rajamani Narayanan

A realistic five-dimensional warped scenario with all standard model fields propagating in the bulk is proposed. Mass hierarchies would in principle be accounted for by judicious choices of the bulk mass parameters, while fermion mixing…

High Energy Physics - Phenomenology · Physics 2016-07-18 Peng Chen , Gui-Jun Ding , Alma. D. Rojas , C. A. Vaquera-Araujo , J. W. F. Valle

We explore the concept of effective alignments: contractions of multiple flavour symmetry breaking flavon fields. These contractions give rise to directions that are hard or impossible to obtain directly by breaking the flavour symmetry.…

High Energy Physics - Phenomenology · Physics 2019-09-04 Ivo de Medeiros Varzielas , Miguel Levy , Ye-Ling Zhou

Flavour symmetries have been used to constrain both quark and lepton mixing parameters. In particular, they can be used to completely fix the mixing angles. For the lepton sector, assuming that neutrinos are Majorana particles, we have…

High Energy Physics - Phenomenology · Physics 2014-10-16 Renato M. Fonseca , Walter Grimus

Electroweak precision data constraints on flavor symmetric vector fields are determined. The flavor multiplets of spin one that we examine are the complete set of fields that couple to quark bi-linears at tree level while not initially…

High Energy Physics - Phenomenology · Physics 2012-01-12 Benjamín Grinstein , Christopher W. Murphy , Michael Trott

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

Lepton Flavor Violating (LFV) observables such as $\mu\to e\gamma$, $\mu\to 3e$ and $\mu N \to eN$ are among the best probes for new physics at the TeV scale. In the near future the bounds on these observables will improve by many orders of…

High Energy Physics - Phenomenology · Physics 2022-11-24 Joan Elias Miro , Clara Fernandez , Mehmet Asim Gumus , Alex Pomarol

Flavor violating processes in the quark and lepton sectors are investigated within a realistic supersymmetric $SO(10)\times A_4$ grand unification model. By employing exotic heavy fermion fields, this model successfully describes various…

High Energy Physics - Phenomenology · Physics 2011-12-30 Abdelhamid Albaid

After briefly reviewing the potential for the $N$-flavor Thirring model, formulated with reducible fermions in 2+1$d$, to exhibit a strongly-coupled UV-stable fixed point where U($2N$) symmetry is spontaneously broken by a fermion bilinear…

High Energy Physics - Lattice · Physics 2023-11-27 Simon Hands , Jude Worthy

For a large set of flavor symmetries, the lowest-dimensional baryon- or lepton-number violating operators in the Standard Model effective field theory (SMEFT) with flavor symmetry are of mass dimension 9. As a consequence, baryon- and…

High Energy Physics - Phenomenology · Physics 2019-12-04 Andreas Helset , Andrew Kobach

We consider lepton flavour violating decays of the top quark, mediated by four-fermion operators. We compile constraints on a complete set of SU(3)*U(1)-invariant operators, arising from their loop contributions to rare decays and from…

High Energy Physics - Phenomenology · Physics 2015-10-28 Sacha Davidson , Michelangelo L. Mangano , Stephane Perries , Viola Sordini

The non-unitarity of the effective leptonic mixing matrix at low energies is a generic signal of extensions of the Standard Model (SM) with extra fermionic singlet particles, i.e. sterile or right-handed neutrinos, to account for the…

High Energy Physics - Phenomenology · Physics 2015-06-22 Stefan Antusch , Oliver Fischer

New heavy neutral leptons lead to non-unitary effects in models for neutrino masses. Such effects could represent a sign of new physics beyond the Standard Model, leading to observable deviations in neutrino oscillation experiments, lepton…

High Energy Physics - Phenomenology · Physics 2024-08-26 Jesús Miguel Celestino-Ramírez , G. Hernández-Tomé , O. G. Miranda , Eduardo Peinado

Upcoming experiments will improve the reach for the lepton flavour violating (LFV) processes $\mu \to e \gamma$, $\mu \to e \bar{e} e$ and $\mu A \to e A$ by orders of magnitude. We investigate whether this upcoming data could rule out some…

High Energy Physics - Phenomenology · Physics 2024-01-18 Marco Ardu , Sacha Davidson , Stéphane Lavignac