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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

Measurements of electroweak precision observables at future electron-positron colliders, such as the CEPC, FCC-ee, and ILC, will be sensitive to physics at multi-TeV scales. To achieve this sensitivity, precise predictions for the Standard…

High Energy Physics - Phenomenology · Physics 2021-04-07 Lisong Chen , Ayres Freitas

We derive the low-energy electroweak effective lagrangian for the case of additional heavy, unmixed, sequential fermions. Present data still allow for the presence of a new quark and/or lepton doublet with masses greater than $M_Z/2$,…

High Energy Physics - Phenomenology · Physics 2009-10-28 F. Feruglio , A. Masiero , S. Rigolin , R. Strocchi

Collider measurements on electroweak physics are summarised. Although the precision on some observables is very high, no deviation from the Standard Model of electroweak interactions is observed. The data allow to set stringent limits on…

High Energy Physics - Experiment · Physics 2008-11-26 Klaus Moenig

The utility of precision electroweak measurements for predicting the Standard Model Higgs mass via quantum loop effects is discussed. Current constraints from $m_W$ and $\sinsthw\mzms$ imply a relatively light Higgs $\lsim 154$ GeV which is…

High Energy Physics - Phenomenology · Physics 2007-05-23 William J. Marciano

After briefly remarking on alternatives for breaking the electroweak symmetry, I discuss the implication that recent precision experiments at LEP have for the symmetry breaking sector. The difficulties associated with generating fermion…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. D. Peccei

This is a pedagogical and self-contained review on obtaining electroweak precision constraints on TeV scale new physics using the effective theory method. We identify a set of relevant effective operators in the standard model and calculate…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhenyu Han

An extension of the Standard Model is presented that leads to the possible existence of new gauge bosons with masses in the range of a few TeV. Due to the fact that their couplings to Standard Model fermions are strongly suppressed, it is…

High Energy Physics - Phenomenology · Physics 2018-10-31 Carlos Alvarado , Alfredo Aranda

The Standard Model global fit to precision data is excellent. The Minimal Supersymmetric Standard Model can also fit the data well, though not as well as the Standard Model. At best, supersymmetric contributions either decouple or only…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jens Erler , Damien M. Pierce

This paper is an updated version of the invited plenary talk given at the XXII Physics in Collision Conference at Stanford, (June 2002). The measurements performed at LEP and SLC have substantially improved the precision of the tests of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Frederic Teubert

The light slepton-sneutrino scenario with non-universal scalar masses at the GUT scale is preferred by the electroweak precision data. Though a universal soft breaking mass at or below the Plank scale can produce the required…

High Energy Physics - Phenomenology · Physics 2009-11-07 Amitava Datta , Abhijit Samanta

A realistic technicolor model is presented with the dynamics below $150$ TeV treated explicitly. Electroweak symmetry is broken by the condensates of a `minimal' doublet of technifermions. The new feature of the model is that the the third…

High Energy Physics - Phenomenology · Physics 2009-09-15 Raman Sundrum

We consider an extension of the standard electroweak theory with gauge group $SU(2)_L \times SU(2)_R \times U(1)_{\tilde{Y}}$, where the gauge bosons of the extra $SU(2)_R$ factor do not couple to ordinary fermions. We show that precision…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Donini , F. Feruglio , J. Matias , F. Zwirner

We study constraints on Composite Higgs models with fermion partial compositeness from electroweak precision measurements, including the 2022 $W$-boson mass result from the CDF collaboration. We focus on models where the Composite Higgs…

High Energy Physics - Phenomenology · Physics 2023-04-12 Mads T. Frandsen , Martin Rosenlyst

We investigate the phenomenological implications of a light scalar bottom quark, with a mass of about the bottom quark mass, within the minimal supersymmetric standard model. The study of such a scenario is of theoretical interest, since,…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Carena , S. Heinemeyer , C. E. M. Wagner , G. Weiglein

At LEP2 many Standard Model predictions are tested up to centre-of-mass energies of 209 GeV. Fermion pair production cross sections and asymmetries agree well with the theoretical expectation over the entire energy range. The measurements…

High Energy Physics - Experiment · Physics 2007-05-23 Stephan Wynhoff

The proposed electron-proton collider experiments LHeC and FCC-eh at CERN are the highest resolution microscopes that can be realised in the present century and they would represent a really unique research facility. We exploit simulated…

High Energy Physics - Phenomenology · Physics 2022-03-15 Daniel Britzger , Max Klein , Hubert Spiesberger

This is a short review of present and future limits on new neutral gauge bosons, in particular on hadrophilic or leptophobic $Z'$s recently proposed to interpret the observed fluctuations of $\Gamma _{c,b}$ at LEP. Light gauge bosons…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. del Aguila , M. Masip , M. Perez-Victoria

The present report of the RF2 Topical Group to Snowmass 2021 describes the physics case for the studies of weak decays of strange and light quarks. Ongoing and proposed precision measurements of kaon, hyperon, pion and $\eta^{(\prime)}$…

High Energy Physics - Experiment · Physics 2022-09-16 Evgueni Goudzovski , Emilie Passemar

A global analysis is performed using the latest data from LEP and SLC. Constraints on the electroweak universal parameters ($S,T,U$) and on the masses of the top quark and Higgs boson within the Standard Model (SM) are investigated. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Seiji Matsumoto