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Related papers: Flavor Constraints from Unitarity and Analyticity

200 papers

The constraints on the mixing angles of the standard fermions with new heavy particles that can appear in many extensions of the electroweak theory are reviewed. Some emphasis is put in distinguishing the effects of a mixing with new states…

High Energy Physics - Phenomenology · Physics 2007-05-23 Enrico Nardi

We implement a systematic effective field theory approach to the benchmark process $\mu\to e \gamma$, performing automated one-loop computations including dimension 6 operators and studying their anomalous dimensions. We obtain limits on…

High Energy Physics - Phenomenology · Physics 2014-10-09 Giovanni Marco Pruna , Adrian Signer

We argue that lepton flavor violating (LFV) decays $M \to \ell_1 \overline{\ell}_2$ of meson states $M$ with different quantum numbers could be used to put constraints on the Wilson coefficients of effective operators describing LFV…

High Energy Physics - Phenomenology · Physics 2017-10-03 Derek E. Hazard

We study the recently found anomalies in $B$-meson decays within a scenario with a warped extra dimension where the Standard Model fermions are propagating in the bulk. The anomalies are then interpreted as the result of the exchange of…

High Energy Physics - Phenomenology · Physics 2017-09-18 Eugenio Megias , Mariano Quiros , Lindber Salas

We present an updated and improved global fit analysis of precision and flavor observables so as to derive constraints on deviations from unitarity in the leptonic mixing matrix. We focus on the case in which these deviations are sourced by…

High Energy Physics - Phenomenology · Physics 2024-05-24 Daniel Naredo-Tuero

Electroweak precision observables (EWPO) measured at the W and Z poles provide stringent limits on possible beyond the Standard Model physics scenarios. In an effective field theory (EFT) framework, the next-to-leading order QCD and…

High Energy Physics - Phenomenology · Physics 2022-05-04 Sally Dawson , Pier Paolo Giardino

We numerically study QCD with a single quark flavour on the lattice probing predictions from effective field theories that are equivalent to minimal super-symmetric Yang-Mills theory in the large $N_c$ limit. The hadronic spectrum including…

High Energy Physics - Lattice · Physics 2021-11-25 Michele Della Morte , Benjamin Jäger , Francesco Sannino , J. Tobias Tsang , Felix P. G. Ziegler

The flavour lepton symmetry is gauged for both the Standard Model flavor group and its extension with three degenerate right-handed neutrinos. As a consequence of anomaly cancellation, exotic leptons are introduced which induce a see-saw…

High Energy Physics - Phenomenology · Physics 2017-05-18 P. Quilez

We examine the contributions to rare processes that arise in models where the Standard Model fermions are localized at distinct points in compact extra dimensions. Tree-level flavor changing neutral current interactions for the Kaluza-Klein…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ben Lillie , JoAnne Hewett

A grand unified $SU(5)$ theory is constructed with a hierarchical breaking of a $U(2)$ flavor symmetry. The small parameters of the squark and slepton mass matrices, necessary to solve the supersymmetric flavor-changing problem, and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Riccardo Barbieri , Lawrence Hall

Gauged extensions [$SU(2)_L\otimes U(1)_Y\otimes U(1)_X$] of the standard $SU(2)_L\otimes U(1)_Y$ model obtained without extending the fermion content of the model are studied. Models that are possible when $U(1)_X$ is identified with some…

High Energy Physics - Phenomenology · Physics 2009-10-28 Gautam Dutta , K. B. Vijaykumar , Anjan S. Joshipura

In the absence of direct evidence of new physics, any ultraviolet theory can be reduced to its specific set of low-energy effective operators. As a case study, we derive the effective field theory for the seesaw extension of the Standard…

High Energy Physics - Phenomenology · Physics 2021-10-19 Rupert Coy , Michele Frigerio

U(1)-family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mario E. Gomez

We study flavor violation in a supersymmetric SU(5) grand unification scenario in a model-independent way employing mass insertions. We examine how the quark and the lepton sector observables restrict sfermion mixings. In many cases, a…

High Energy Physics - Phenomenology · Physics 2007-10-25 Jae-hyeon Park

In this paper we present the partial wave unitarity bound in the parameter space of dimension-5 and dimension-6 effective operators that arise in a compositeness scenario. These are routinely used in experimental searches at the LHC to…

High Energy Physics - Phenomenology · Physics 2019-10-25 S. Biondini , R. Leonardi , O. Panella , M. Presilla

We analyze the scattering of fermions, Higgs and electroweak gauge bosons in order to obtain the partial-wave unitarity bounds on dimension-six effective operators, including those involving fermions. We also quantify whether, at the LHC…

High Energy Physics - Phenomenology · Physics 2017-09-13 Tyler Corbett , O. J. P. Éboli , M. C. Gonzalez-Garcia

We estimate the sensitivity of Wilson coefficients of the lepton flavor-violating dimension-six operators at the proposed $\mu^+\mu^-$ collider. We compute the signal significance at $\sqrt{s}$ = 3 and 10 TeV, respectively, with an…

High Energy Physics - Phenomenology · Physics 2025-01-28 Sukanta Dutta , Purnath Unnikrishnan , Yashasvi

We study the modular symmetric standard-model effective field theory. We employ the stringy Ansatz on coupling structure that 4-point couplings $y^{(4)}$ of matter fields are written by a product of 3-point couplings $y^{(3)}$ of matter…

High Energy Physics - Phenomenology · Physics 2022-04-06 Tatsuo Kobayashi , Hajime Otsuka , Morimitsu Tanimoto , Kei Yamamoto

Minimal Flavour Violation in its strong or weak versions, based on $U(3)^3$ and $U(2)^3$ respectively, allows suitable extensions of the Standard Model at the TeV scale to comply with current flavour constraints in the quark sector. Here we…

High Energy Physics - Phenomenology · Physics 2016-01-27 Riccardo Barbieri , Fabrizio Senia

Grand unified theories with fermions transforming as irreducible representations of a discrete nonabelian flavor symmetry can lead to realistic fermion masses, without requiring very small fundamental parameters. We construct a specific…

High Energy Physics - Phenomenology · Physics 2013-11-13 David B. Kaplan , Martin Schmaltz