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Related papers: The CKM parameters in the SMEFT

200 papers

Charged lepton flavour-violating (cLFV) processes, which are definite proof of new physics beyond the Standard Model, have remained elusive experimentally till now. Effective Field Theory (EFT) has been very useful in providing information…

High Energy Physics - Phenomenology · Physics 2026-01-06 Utpal Chattopadhyay , Debottam Das , Rahul Puri , Joydeep Roy

Whenever an anomaly in the flavour sector appears, analyses are performed examining whether it can be explained by adding a small number of carefully-chosen flavour non-universal four-fermion SMEFT operators. These analyses are typically…

High Energy Physics - Phenomenology · Physics 2026-03-05 Alakabha Datta , Jean-François Fortin , Jacky Kumar , David London , Danny Marfatia , Nicolas Sanfaçon

From general analyticity and unitarity requirements on the UV theory, positivity bounds on the Wilson coefficients of the dimension-8 operators composed of 4 fermions and two derivatives appearing in the Standard Model Effective Field…

High Energy Physics - Phenomenology · Physics 2021-06-30 Quentin Bonnefoy , Emanuele Gendy , Christophe Grojean

Treating the MSSM as an effective theory below a threshold scale Lambda, we study the consequences of having dimension-five operators in the superpotential for flavour and CP-violating processes. Below the supersymmetric threshold such…

High Energy Physics - Phenomenology · Physics 2008-11-26 Maxim Pospelov , Adam Ritz , Yudi Santoso

The combination of precise experimental measurements and theoretical predictions allows to extract Cabibbo-Kobayashi-Maskawa (CKM) matrix elements or constrain flavor changing processes in the standard model. Focusing at theoretical…

High Energy Physics - Phenomenology · Physics 2024-09-05 Oliver Witzel

We compute the leading-logarithmic correction to the neutrino mass matrix in the Standard Model effective field theory (SMEFT) to dimension seven. In the limit of negligible lepton and down-type quark Yukawa couplings, it receives…

High Energy Physics - Phenomenology · Physics 2021-08-06 Mikael Chala , Arsenii Titov

The Standard Model Effective Field Theory (SMEFT) is a powerful tool to search for new physics in a model-independent way. We explore the synergies arising from different types of observables in a combined, global SMEFT fit. Specifically,…

High Energy Physics - Phenomenology · Physics 2023-07-13 Cornelius Grunwald , Gudrun Hiller , Kevin Kröninger , Lara Nollen

We present comprehensive global fits of the SMEFT under the $\textit{minimal}$ minimal flavour violation (MFV) hypothesis, i.e. assuming that only the flavour-symmetric and CP-invariant operators are relevant at the high scale. The…

High Energy Physics - Phenomenology · Physics 2023-12-07 Riccardo Bartocci , Anke Biekötter , Tobias Hurth

New physics not far above the TeV scale should leave a pattern of virtual effects in observables at lower energies. What do these effects tell us about the flavor structure of a UV theory? Within the framework of Standard Model Effective…

High Energy Physics - Phenomenology · Physics 2021-06-16 Sebastian Bruggisser , Ruth Schäfer , Danny van Dyk , Susanne Westhoff

The CP properties of effective operators are closely related to the spacetime and internal symmetries, such as the flavor symmetry, in the standard model effective field theory (SMEFT). In this work, we utilize the flavor symmetry to…

High Energy Physics - Phenomenology · Physics 2025-02-07 Hao Sun , Jiang-Hao Yu

In the framework of the Standard Model Effective Field Theory, we compare the lower bounds on the scale of new physics possibly contributing to the $f\bar{f}h$ effective couplings, obtained from the measurements of different observables,…

High Energy Physics - Phenomenology · Physics 2022-05-25 J. Alonso-Gonzalez , A. de Giorgi , L. Merlo , S. Pokorski

We report codes for the Standard Model Effective Field Theory (SMEFT) in FeynRules -- the SMEFTsim package. The codes enable theoretical predictions for dimension six operator corrections to the Standard Model using numerical tools, where…

High Energy Physics - Phenomenology · Physics 2019-08-12 Ilaria Brivio , Yun Jiang , Michael Trott

The standard model of electroweak interactions is reviewed, stressing the top quark's impact on precision tests and on determination of parameters of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Some opportunities for the study of CP…

High Energy Physics - Phenomenology · Physics 2009-09-25 J. Rosner

The $U(3)^5$ symmetry within the SMEFT framework restricts the inclusion of only fully flavor-conserving operators at dimension six. This proceeding presents a global analysis of the SMEFT under this assumption. We provide global…

High Energy Physics - Phenomenology · Physics 2024-05-17 Riccardo Bartocci

We present the status of the CKM matrix parameters in the framework of the Standard Model. We perform a model independent analysis to set constraints on additional effective parameters accounting for possible New Physics effects and to…

High Energy Physics - Phenomenology · Physics 2009-05-25 Vincent Tisserand

In these proceedings I present a personal perspective of the challenges for new physics (NP) searches in the flavour sector. Since the CKM mechanism of flavour violation has been established to a very high precision, we know that physics…

High Energy Physics - Phenomenology · Physics 2014-09-12 Andreas Crivellin

We present a global likelihood function in the space of dimension-six Wilson coefficients in the Standard Model Effective Field Theory (SMEFT). The likelihood includes contributions from flavour-changing neutral current B decays, lepton…

High Energy Physics - Phenomenology · Physics 2019-07-24 Jason Aebischer , Jacky Kumar , Peter Stangl , David M. Straub

Predictions of the Cabibbo-Kobayashi-Maskawa (CKM) parameters are investigated in detail in recent predictive models which are based on low-energy non-abelian discrete family symmetries. Some of the models can already be excluded at the…

High Energy Physics - Phenomenology · Physics 2010-01-13 Takeshi Araki , Jisuke Kubo

We study the implications of the recent measurements of $R_K$ and $R_{K^*}$ by the LHCb collaboration. We do that by adopting a model-independent approach based on the Standard Model Effective Field Theory (SMEFT), in which the dominant new…

High Energy Physics - Phenomenology · Physics 2017-08-30 Alejandro Celis , Javier Fuentes-Martin , Avelino Vicente , Javier Virto

The CKM matrix, V, relates the quark mass and flavor bases. In the standard model, V is unitary 3X3, and specified by four arbitrary parameters, including a phase allowing for $CP$ violation. We review the experimental determination of V,…

High Energy Physics - Experiment · Physics 2016-11-23 Frank C. Porter