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Related papers: A flavour physics scenario for the 750 GeV diphoto…

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We study a non-universal flavor scenario at the level of the Standard Model Effective Field Theory, according to which the matrix of Wilson coefficients $c_{uW}$ of an up-type electroweak quark dipole operator is aligned with the up-type…

High Energy Physics - Phenomenology · Physics 2024-11-26 Quentin Bonnefoy , Jonathan Kley , Di Liu , Alejo N. Rossia , Chang-Yuan Yao

The existence of anomalous electric($\tilde \kappa$) and/or magnetic($\kappa$) dipole moment couplings between the heavy flavor fermions ($c,b,\tau$) and the $Z$ boson can cause significant shifts in the values of several electroweak…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas G. Rizzo

We construct a model of quark-lepton unification at the TeV scale based on an $SU(4)$ gauge symmetry, while still having acceptable neutrino masses and enough suppression in flavor changing neutral currents. An approximate $U(2)$ flavor…

High Energy Physics - Phenomenology · Physics 2018-05-16 Admir Greljo , Ben A. Stefanek

This letter gathers a selection of Standard Model predictions issued from the metrology of the CKM parameters performed by the CKMfitter group. The selection includes purely leptonic decays of neutral and charged B, D and K mesons. In the…

High Energy Physics - Phenomenology · Physics 2011-09-08 J. Charles , O. Deschamps , S. Descotes-Genon , R. Itoh , H. Lacker , A. Menzel , S. Monteil , V. Niess , J. Ocariz , J. Orloff , S. T'Jampens , V. Tisserand , K. Trabelsi

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

We present a supersymmetric flavour model based on the T' discrete group, which explains fermion masses and mixings. The flavour symmetry, acting in the supersymmetric sector, provides well defined sfermion mass matrices and the resulting…

High Energy Physics - Phenomenology · Physics 2011-08-24 Luca Merlo

A composite Higgs boson of 125 GeV mass, only mildly fine-tuned, requires top partners with a semi-perturbative coupling and a mass not greater than about a TeV. We analyze the strong constraints on such picture arising from flavour and…

High Energy Physics - Phenomenology · Physics 2015-06-12 Riccardo Barbieri , Dario Buttazzo , Filippo Sala , David M. Straub , Andrea Tesi

A new heavy resonance may be observable at the LHC if it has a significant decay branching fraction into a pair of photons. We entertain this possibility by looking at the modest excess in the diphoton invariant mass spectrum around 750 GeV…

High Energy Physics - Phenomenology · Physics 2017-01-17 Amine Ahriche , Gaber Faisel , Salah Nasri , Jusak Tandean

Among different measured observables of top-antitop quark pairs at hadron colliders, the forward-backward asymmetry ($A_{\text{FB}}$) measured by the CDF and D0 collaborations has inconsistency with the Standard Model prediction. The…

High Energy Physics - Phenomenology · Physics 2013-02-21 Sara Khatibi , Mojtaba Mohammadi Najafabadi

ATLAS and CMS have each reported a modest diphoton excess consistent with the decay of a broad resonance at ~ 750 GeV. We show how this signal can arise in a weakly coupled theory comprised solely of narrow width particles. In particular,…

High Energy Physics - Phenomenology · Physics 2015-12-29 Haipeng An , Clifford Cheung , Yue Zhang

Light dark matter with flavor-violating couplings to fermions may be copiously produced in the laboratory as missing energy from decays of SM particles. Here we study the effective Lagrangian of a light dark vector with generic dipole or…

High Energy Physics - Phenomenology · Physics 2024-05-02 Jordi Folch Eguren , Sophie Klingel , Emmanuel Stamou , Mustafa Tabet , Robert Ziegler

The recent results from the Fermilab muon $g-2$ experiment, as well as the persisting hints of lepton flavor universality violation in $B$-meson decays, present a very strong case for flavor-nonuniversal new physics beyond the Standard…

High Energy Physics - Phenomenology · Physics 2022-07-18 P. S. Bhupal Dev , Amarjit Soni , Fang Xu

The collection of a few anomalies in semileptonic $B$-decays invites to speculate about the emergence of some strikingly new phenomena. Here we offer a possible interpretation of these anomalies in the context of a weakly broken $U(2)^5$…

High Energy Physics - Phenomenology · Physics 2016-03-23 Riccardo Barbieri , Gino Isidori , Andrea Pattori , Fabrizio Senia

Recently Nelson et al. proposed an interesting flavor symmetric model to account for the top quark forward-backward asymmetry and the dijet anomaly at CDF simultaneously with just three parameters: a coupling constant of order one, and two…

High Energy Physics - Phenomenology · Physics 2011-08-31 Guohuai Zhu

The flavour puzzle is one of the greatest mysteries in particle physics. A `flavour deconstruction' of the electroweak gauge symmetry, by promoting at least part of it to the product of a third family factor (under which the Higgs is…

High Energy Physics - Phenomenology · Physics 2023-11-03 Joe Davighi , Ben A. Stefanek

The dimuon and dielectron data from the Tevatron $\bar pp$ collider are used to probe for heavy quarks, which decay dominantly via flavour changing neutral current. Depending on whether the $FCNC$ decay occurs at the tree or loop level, one…

High Energy Physics - Phenomenology · Physics 2008-11-26 Biswarup Mukhopadhyaya , D. P. Roy

Charged-lepton flavor violation (CLFV) is a smoking-gun signature of physics beyond the Standard Model. The discovery of CLFV in upcoming experiments would indicate that CLFV processes must have been efficient in the early Universe at…

High Energy Physics - Phenomenology · Physics 2022-07-13 Kyohei Mukaida , Kai Schmitz , Masaki Yamada

The ATLAS and CMS experiments at the LHC have reported the observation of a possible excess of events corresponding to a new particle $h$ with mass $\sim 125$ GeV that might be the long-sought Higgs boson, or something else. Decyphering the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Gianluca Blankenburg , John Ellis , Gino Isidori

The singly charged $SU(2)_L$ singlet scalar, with its necessarily flavour violating couplings to leptons, lends itself particularly well for an explanation of the Cabibbo Angle Anomaly and of hints for lepton flavour universality violation…

High Energy Physics - Phenomenology · Physics 2021-05-17 Fiona Kirk

We propose a twin Pati-Salam (PS) theory of flavour broken to the $G_{4321}$ gauge group at high energies, then to the Standard Model at low energies, yielding a TeV scale vector leptoquark $U^{\mu}_1(3,1,2/3)$ which has been suggested to…

High Energy Physics - Phenomenology · Physics 2021-11-24 Stephen F. King