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Related papers: One-Loop Calculation of the Oblique S Parameter in…

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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

Electroweak precision data have been extensively used to constrain models containing physics beyond that of the Standard Model. When the model contains Higgs scalars in representations other than singlets or doublets, and hence rho not…

High Energy Physics - Phenomenology · Physics 2014-11-18 Mu-Chun Chen , Sally Dawson , Tadas Krupovnickas

We derive dispersion relations for the electroweak oblique observables measured at LEP in the context of $SO(5)/SO(4)$ composite Higgs models. It is shown how these relations can be used and must be modified when modeling the spectral…

High Energy Physics - Phenomenology · Physics 2015-12-23 Roberto Contino , Matteo Salvarezza

The parametrization of the oblique corrections through $S$, $T$, and $U$ -- later extended by $V$, $W$, and $X$ -- is a convenient way of comparing the predictions for various electroweak observables at the one-loop level between the…

High Energy Physics - Phenomenology · Physics 2024-07-09 Simonas Draukšas , Vytautas Dūdėnas , Luís Lavoura

Electroweak precision measurements can provide indirect information about the possible scale of supersymmetry already at the present level of accuracy. We update the present-day sensitivities of precision data using the new experimental…

High Energy Physics - Phenomenology · Physics 2009-11-11 J. Ellis , S. Heinemeyer , K. A. Olive , G. Weiglein

A complete analysis of the electroweak precision observables is performed within a recently proposed minimal composite Higgs model, realized as a 5-dimensional warped compactification. In particular, we compute Z->bb and the one-loop…

High Energy Physics - Phenomenology · Physics 2011-05-05 Kaustubh Agashe , Roberto Contino

We explore the one-loop electroweak radiative corrections in the minimal $SU(5)$ and the no-scale flipped $SU(5)$ supergravity models via explicit calculation of vacuum polarization contributions to the $\epsilon_{1,2,3}$ parameters.…

High Energy Physics - Phenomenology · Physics 2009-10-22 J. Lopez , D. V. Nanopoulos , G. Park , H. Pois , K. Yuan

An electroweak model in which the masses of the W and Z bosons and the fermions are generated by quantum loop graphs through a symmetry breaking is investigated. The model is based on a regularized quantum field theory in which the quantum…

High Energy Physics - Phenomenology · Physics 2009-08-07 J. W. Moffat , V. T. Toth

We compute the upper bound on the mass of the lightest Higgs boson in the Minimal Supersymmetric Standard Model in a model-independent way, including leading (one-loop) and next-to-leading order (two-loop) radiative corrections. We find…

High Energy Physics - Phenomenology · Physics 2011-05-05 J. A. Casas , J. R. Espinosa , M. Quirós , A. Riotto

The LEP data and the measurement of $M_W$ confirm the electro weak symmetry breaking by the Higgs mechanism with (2--3)\% accuracy. For the Higgs boson mass, fits to the present data (without the SLD result) give $M_h=121^{+207}_{-118}$ GeV…

High Energy Physics - Phenomenology · Physics 2009-10-28 P. H. Chankowski , S. Pokorski

We perform a manifestly gauge-independent analysis of the vacuum stability in the Standard Model (SM) including two-loop matching, three-loop renormalization group evolution, and pure QCD corrections through four loops. All these…

High Energy Physics - Phenomenology · Physics 2015-11-18 A. V. Bednyakov , B. A. Kniehl , A. F. Pikelner , O. L. Veretin

We investigate the one-loop contributions to S and T oblique parameteres in gauge-Higgs unification. We show that these parameters are finite in five dimensional space-time, but are divergent in more than five dimensions. Remarkably,…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. S. Lim , Nobuhito Maru

We study the electroweak symmetry breaking in a five dimensional $Sp(6)$ gauge-Higgs unification model where the weak mixing angle is predicted to be $\sin^2 \theta_W=1/4$ at the compactification scale. We find that the correct pattern of…

High Energy Physics - Phenomenology · Physics 2025-03-11 Nobuhito Maru , Akio Nago

We review the empirical evidence for the validity of the Standard Electroweak Theory in Nature. The experimental data are interpreted in terms of an effective Lagrangian for Z physics, allowing for potential sources of SU(2) violation and…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Schildknecht

A reexamination is made of one-loop oblique electroweak corrections. General definitions are given of the oblique parameters without reference to any $q^2$-expansion scheme. The old oblique parameters S,T and U are defined as differences of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Anirban Kundu , Probir Roy

We study the impact of LEP2 constraints on the dimensionless coefficients of the electroweak chiral Lagrangian on the precision observables using the improved renormalization group equations. We find that the current uncertainty in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sukanta Dutta , Kaoru Hagiwara , Qi-Shu Yan

We present an effective Lagrangian parameterization describing scalar, vector, and axial-vector bound states, originating from a strong breaking of the electroweak symmetry, based on the global symmetry $SU(N)_L\otimes SU(N)_R$. In this…

High Energy Physics - Phenomenology · Physics 2015-05-18 R. Casalbuoni , A. Deandrea , S. De Curtis , N. Di Bartolomeo , D. Dominici , F. Feruglio , R. Gatto

We study Radiative Electroweak Symmetry Breaking in the Minimal Supersymmetric Standard Model (MSSM). We employ the 2-loop Renormalization Group equations for running masses and couplings taking into account sparticle threshold effects. The…

High Energy Physics - Phenomenology · Physics 2009-09-24 A. Dedes , A. B. Lahanas , K. Tamvakis

We propose a new model of 5D $SU(3)\otimes U(1)_X$ gauge-Higgs unification with a successful electroweak symmetry breaking and a realistic Higgs boson mass. In our model, the representations of the fermions are very simple, the ${\bf 3},…

High Energy Physics - Phenomenology · Physics 2018-07-25 Yuki Adachi , Nobuhito Maru

We suggest the so-called bosonic seesaw mechanism in the context of a classically conformal $U(1)_{B-L}$ extension of the Standard Model with two Higgs doublet fields. The $U(1)_{B-L}$ symmetry is radiatively broken via the Coleman-Weinberg…

High Energy Physics - Phenomenology · Physics 2015-09-08 Naoyuki Haba , Hiroyuki Ishida , Nobuchika Okada , Yuya Yamaguchi