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Related papers: Lepton non-universality at LEP and charged Higgs

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We study the effect of a light charged Higgs appearing in supersymmetric models containing two Higgs doublets on the measurement of leptonic branching ratios of the W boson at LEP. We show that the $2.8 \sigma$ excess of the branching ratio…

High Energy Physics - Phenomenology · Physics 2008-07-22 Radovan Dermisek

We study constraints on type-II two Higgs doublet models at large tan{beta} from LEP/SLD Z-pole data and from lepton universality violation in W decay. We perform a global fit and find that, in the context of Z decay, the LEP/SLD…

High Energy Physics - Phenomenology · Physics 2007-05-23 Oleg Lebedev , Will Loinaz , Tatsu Takeuchi

We investigate whether the $2.6\sigma$ deviation from lepton flavour universality in $B^+\to K^+\ell^+\ell^-$ decays recently observed at the LHCb experiment can be explained in minimal composite Higgs models. We show that a visible…

High Energy Physics - Phenomenology · Physics 2015-08-10 Christoph Niehoff , Peter Stangl , David M. Straub

There exist about $3.7\sigma$ positive and $2.4\sigma$ negative deviations in the muon and electron anomalous magnetic moments ($g-2$). Also, some ratios for lepton universality in $\tau$ decays have almost $2\sigma$ deviations from the…

High Energy Physics - Phenomenology · Physics 2019-05-29 Xiao-Fang Han , Tianjun Li , Lei Wang , Yang Zhang

We investigate the constraint on the split fermions in extra dimensions by considering the universality of $W$ leptonic decays $W\to l_i \nu_i$, the charged lepton decays $l_i \ra l_j\nu_i\bar{\nu}_j$, and the lepton flavor violating…

High Energy Physics - Phenomenology · Physics 2009-11-07 We-Fu Chang , I-Lin Ho , John N. Ng

Lepton generation universality holds very well in Z decays, but appears to be violated in recent LEP data of W leptonic decay branching fractions. If this trend persists, a consistent and natural explanation is a model of generation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiao-Yuan Li , Ernest Ma

In several extensions of the Standard Model, the top quark can decay into a bottom quark and a light charged Higgs boson H+, t to bH+, in addition to the Standard Model decay t to bW. Since W bosons decay to the three lepton generations…

High Energy Physics - Experiment · Physics 2013-06-11 ATLAS Collaboration

We discuss the Type-X (lepton-specific) two Higgs doublet model as a solution of the anomaly of the muon $g-2$. We consider various experimental constraints on the parameter space such as direct searches for extra Higgs bosons at the LEP II…

High Energy Physics - Phenomenology · Physics 2015-11-04 Tomohiro Abe , Ryosuke Sato , Kei Yagyu

We describe a possibility to explain the $2.6\sigma$ deviation from lepton flavour universality observed by the LHCb collaboration in $B^+\to K^+\ell^+\ell^-$ decays in the context of minimal composite Higgs models. We find that a sizable…

High Energy Physics - Phenomenology · Physics 2015-10-16 Peter Stangl

The ratio of branching ratios of the $W$ boson to muons and electrons, $R^{\mu/e}_W=B(W\rightarrow \mu\nu)/B(W\rightarrow e\nu)$, has been measured using 140 fb$^{-1}$ of $pp$ collision data at $\sqrt{s}=13$ TeV collected with the ATLAS…

High Energy Physics - Experiment · Physics 2024-10-03 ATLAS Collaboration

A search for pair-produced charged Higgs bosons was performed in the data collected by the DELPHI detector at LEP II at centre-of-mass energies from 189 GeV to 209 GeV. Five different final states, tau+ nu_tau tau- anti-nu_tau, c sbar cbar…

High Energy Physics - Experiment · Physics 2008-11-26 The DELPHI Collaboration , J. Abdallah

A new evaluation of the charged Higgs boson decay $H^+ -> W^+\gamma$ is presented in the context of the general two-Higgs doublet model. A nonlinear $R_\xi$-gauge which considerably simplifies the calculation is introduced and simple…

High Energy Physics - Phenomenology · Physics 2011-07-19 J. Hernandez-Sanchez , M. A. Perez , G. Tavares-Velasco , J. J. Toscano

The production of lepton pairs in the Higgs boson decay $h \to \ell^+ \ell^- \gamma$ is studied. The emphasis is put on the structure of the Higgs boson interaction with the fermions. This interaction is chosen as a mixture of the scalar…

High Energy Physics - Phenomenology · Physics 2020-06-18 V. A. Kovalchuk , A. Yu. Korchin

Using a sample of 122 million Upsilon(3S) decays collected with the BaBar detector at the PEP-II asymmetric energy collider at the SLAC National Accelerator Laboratory, we measure the ratio…

High Energy Physics - Experiment · Physics 2019-08-13 Elisa Guido

The decay of a Higgs boson into a pair of W bosons h --> W^+W^-, is a dominant mode for Higgs boson masses above 135 GeV. At hadron colliders, searches for this decay focus on channels in which both W bosons decay leptonically into charged…

High Energy Physics - Phenomenology · Physics 2014-11-18 Edmond L. Berger , Zack Sullivan

The one-loop branching ratios for the process Z->h(A)+gamma are calculated in the general Two Higgs Doublet Model (Model II) taking into account existing constraints on the model parameters. For Higgs boson masses below 50 GeV and tan beta…

High Energy Physics - Phenomenology · Physics 2011-07-19 Maria Krawczyk , Jan Zochowski , Peter Mattig

We investigate the differential branching ratio, branching ratio, differential forward-backward asymmetry, the forward-backward asymmetry of the lepton pair and the lepton polarization asymmetry of the exclusive $B\to \tau^+ \tau^- \gamma$…

High Energy Physics - Phenomenology · Physics 2009-11-07 Guray Erkol , Gursevil Turan

We derive model-independent constraints on Higgs mass and couplings from associated signals for higher masses, accessible at LEP2. This work is motivated by the fact that, in many extensions of the standard model, the Higgs boson can have…

High Energy Physics - Phenomenology · Physics 2009-09-17 A. Lopez-Fernandez , J. C. Romão , F. de Campos , J. W. F. Valle

We point out that the discovery of a right-handed charged gauge boson $W_R^\pm$ with mass of around a few TeV, for example through a signal of two leptons and two jets that has been reported by CMS to have a 2.8$\sigma$ local excess or…

High Energy Physics - Phenomenology · Physics 2015-09-02 Mansi Dhuria , Chandan Hati , Raghavan Rangarajan , Utpal Sarkar

For the first time at LEP most of the events will have four fermions in the finals state and we have the unique opportunity of testing a complete calculation with the experimental data, well beyond the usual approximation of computing…

High Energy Physics - Phenomenology · Physics 2009-10-30 Giampiero Passarino
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