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Related papers: Effective operator contributions to the oblique pa…

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The dependence of the T-odd correlation on the effective Lagrangian parameters in the $K^+ \to \pi l \nu \gamma, l=e, \mu$ decays is analyzed. It is shown that the introduced observable is perspective in a search for new physics in the…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. V. Braguta , A. A. Likhoded , A. E. Chalov

The contribution to precision electroweak measurements due to TeV physics which couples primarily to the $W^\pm$ and $Z$ bosons may be parameterized in terms of the three `oblique correction' parameters, S, T and U. We extend this…

High Energy Physics - Phenomenology · Physics 2014-05-16 Ivan Maksymyk , C. P. Burgess , David London

We present a model independent analysis of custodial corrections to the $S$ parameter. The negative contributions coming from direct corrections, i.e. the corrections associated to effects of new physics in the fermionic sector, can be used…

High Energy Physics - Phenomenology · Physics 2014-04-24 Donatello Dolce

We consider extensions of the Standard Model with neutral scalars in multiplets of $SU(2)$ larger than doublets. When those scalars acquire vacuum expectation values, the resulting masses of the gauge bosons $W^\pm$ and $Z^0$ are not…

High Energy Physics - Phenomenology · Physics 2022-07-27 Francisco Albergaria , Luís Lavoura

The applications of effective lagrangians to the determination of the effects of physics beyond the Standard Model are briefly described. Emphasis is given to those effective operators which generate the largest deviations form the Standard…

High Energy Physics - Phenomenology · Physics 2009-09-25 Jose Wudka

We express the oblique parameters $S$, $T$, $U$, $V$, $W$, and $X$ in terms of the corresponding mixing matrices in the framework of three BSM models with three CP-even neutral scalars. We consider three types of the extension of the scalar…

High Energy Physics - Phenomenology · Physics 2025-08-26 Swagata Ghosh

We briefly review the global Standard Model fit to electroweak precision data, and discuss the status of electroweak constraints on new interactions. We follow a general effective Lagrangian approach to obtain model-independent limits on…

High Energy Physics - Phenomenology · Physics 2015-06-16 J. de Blas

We present general expressions for the oblique parameters S, T, U, V, W, and X in the SU(2)xU(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge 1/2, and an arbitrary number of scalar SU(2) singlets.

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Grimus , L. Lavoura , O. M. Ogreid , P. Osland

Probing the properties of the discovered Higgs boson may tell us whether or not it is the same particle as the one predicted by the Standard Model. To this aim we parametrize deviations of the Higgs couplings to matter from the Standard…

High Energy Physics - Phenomenology · Physics 2016-02-22 Hermes Belusca-Maito

We show that an effective field theory that includes non-standard couplings between the electroweak gauge bosons and the top and bottom quarks may yield negative contributions to both the S and T oblique radiative electroweak parameters. We…

High Energy Physics - Phenomenology · Physics 2009-10-30 Bogdan A. Dobrescu , John Terning

Using a chiral Lagrangian we show that strongly interacting models of electroweak symmetry breaking are not in conflict with precision data. Such models, like Technicolor, need not lead to a heavy Higgs-like signal. Furthermore, the allowed…

High Energy Physics - Phenomenology · Physics 2017-08-23 Andreas Nyffeler

We present general formulas for the oblique-correction parameters $S$, $T$, $U$, $V$, $W$, and $X$ in a model of New Physics having arbitrary numbers of scalar leptoquarks of the five permissible types. We allow for a general mixing among…

High Energy Physics - Phenomenology · Physics 2023-08-30 Francisco Albergaria , Luís Lavoura

We review the effective field theory approach to physics beyond the Standard Model using dimension-six operators. Topics include the choice of operator basis, electroweak boson pair production, precision electroweak physics (including…

High Energy Physics - Phenomenology · Physics 2015-06-18 Scott Willenbrock , Cen Zhang

Experiments have confirmed the presence of a mass gap between the Standard Model and potential New Physics. Consequently, the exploration of effective field theories to detect signals indicative of Physics Beyond the Standard Model is of…

High Energy Physics - Phenomenology · Physics 2024-10-22 Ignasi Rosell , Antonio Pich , Juan Jose Sanz-Cillero

In a model independent framework, the effects of new physics at the electroweak scale can be parametrized in terms of an effective Lagrangian expansion. Assuming the $SU(2)_L x U(1)_Y$ gauge symmetry is linearly realized, the expansion at…

High Energy Physics - Phenomenology · Physics 2014-11-21 J. Gonzalez-Fraile

Effective Lagrangians represent an important, model independent tool for studying physics beyond the Standard Model, via its impact on electroweak scale observables. In particular, two different effective descriptions may be appropriate,…

High Energy Physics - Phenomenology · Physics 2015-05-19 Ilaria Brivio

We study the electroweak interactions within the standard electroweak theory in the case where the Higgs particle is heavy, namely, $M_H \leq 1\;TeV$. By integrating out the Higgs boson to one loop we find the complete effective lagrangian,…

High Energy Physics - Phenomenology · Physics 2008-02-03 M. J. Herrero , E. Ruiz Morales

In this article we study the noncommutative description of the DBI Lagrangian and its T-dual counterpart. We restrict the freedoms of the noncommutativity parameters of these Lagrangians. Therefore the noncommutativity parameter, the…

High Energy Physics - Theory · Physics 2020-08-21 Davoud Kamani

We consider the Standard Model as an effective theory at the weak scale $v$ of a generic new strong interaction that dynamically breaks electroweak symmetry at the energy scale $\Lambda\sim $ (few) TeV. Assuming only the minimal field…

High Energy Physics - Phenomenology · Physics 2015-06-04 Gerhard Buchalla , Oscar Cata

We study the effect of the diagonal extended technicolor(ETC) gauge boson on the oblique correction parameters. It is shown that in the $T$ parameter is unacceptably large when the $Zbb$ vertex correction and $S$ parameter are consistent…

High Energy Physics - Phenomenology · Physics 2009-10-28 Tadashi Yoshikawa