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Related papers: Theoretical issues at LEP2 and LC

200 papers

The rapid increase of the e+e- --> W+W- cross section in the threshold region provides a method for measuring M(W) at LEP2. The dependence of the theoretical cross section -- including the effects of the finite W width, Coulomb interactions…

High Energy Physics - Phenomenology · Physics 2016-09-01 W. J. Stirling

Cross-sections and angular distributions for hadronic and lepton pair final states in e+e- collisions at a centre-of-mass energy near 189 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , G. Abbiendi

We derive bounds on Higgs and gauge--boson anomalous interactions using the LEP2 data on the production of three photons and photon pairs in association with hadrons. In the framework of $SU(2)_L \otimes U(1)_Y$ effective Lagrangians, we…

High Energy Physics - Phenomenology · Physics 2009-10-31 O. J. P. Eboli , M. C. Gonzalez-Garcia , S. M. Lietti , S. F. Novaes

We show that in e-e+ colliders at energies above the Z-peak, the process e-e+ to b b(bar) becomes very sensitive to the presence of residual New Physics (NP) effects described by the dim=6 SU(3)*SU(2)*U(1) gauge invariant operators O(qW),…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. J. Gounaris , D. T. Papadamou , F. M. Renard

A conformally invariant hidden sector is considered, with a scalar operator $O$ of low dimension that couples to the electro-weak gauge bosons of the Standard Model, via terms such as $O F^{\mu\nu}F_{\mu\nu}$. By examining single photon…

High Energy Physics - Phenomenology · Physics 2011-08-08 Scott Kathrein , Simon Knapen , Matthew J. Strassler

Progress continues on many fronts of experimental testing of electroweak symmetry breaking. Updates were presented on LEP, SLC, Brookhaven g-2 ring, Tevatron Collider, HERA, CESR and Tevatron neutrino experiments. Perhaps most exciting is…

High Energy Physics - Experiment · Physics 2007-05-23 L. Nodulman

We present a refined and expanded analysis of the CDF $ee\gamma\gamma + \Et$ event as superpartner production, assuming the lightest neutralino is the lightest supersymmetric particle. A general low-energy Lagrangian is constrained by a…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. Ambrosanio , G. L. Kane , Graham D. Kribs , Stephen P. Martin , S. Mrenna

Data from high-energy physics experiments are collected with significant financial and human effort and are mostly unique. However, until recently no coherent strategy existed for data preservation and re-use, and many important and complex…

High Energy Physics - Experiment · Physics 2015-06-03 Roman Kogler , David M. South , Michael Steder

A summary is given of the current status of measurements of the strong coupling constant $\alpha_s$ performed at LEP. These include measurements from inclusive observables as well as from event shape variables. Recent results based on power…

High Energy Physics - Experiment · Physics 2007-05-23 G. Dissertori

$W$ boson pair production processes at $e^+e^-$ and $pp$ colliders have been conventionally interpreted as measurements of $WWZ$ and $WW\gamma$ triple gauge couplings (TGCs). Such interpretation is based on the assumption that new physics…

High Energy Physics - Phenomenology · Physics 2017-11-17 Zhengkang Zhang

Results on the cross section measurement of Z boson pair-production at LEP are presented. The more general case of neutral-current four-fermion production and the particular case of ZZ events enriched in b quarks are also discussed. All the…

High Energy Physics - Experiment · Physics 2007-05-23 Salvatore Mele

We update the uncertainty analysis on $S$ parameter of the electroweak chiral Lagrangian (EWCL) by including the LEP-II W pair production data. We find that experimental data still allow a positive $S^{EXP}(1\textrm{TeV})$.

High Energy Physics - Phenomenology · Physics 2017-08-23 Qi-Shu Yan

The investigation of W-pair production offers unique precision tests of the electroweak theory at future e+e- colliders, including precise determinations of cross sections, the W-boson mass, and gauge-boson self-couplings. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Denner , S. Dittmaier , M. Roth , D. Wackeroth

The theoretical background of the electroweak precision measurements at LEP1 is reviewed. The presentation is compact but specific enough to understand all details.

High Energy Physics - Phenomenology · Physics 2007-05-23 Bodo Lampe

The pair production cross section for scalar and vector leptoquarks at $ep$ colliders is calculated for the case of photon--gluon fusion. In a model independent analysis we consider the most general $C$ and $P$ conserving couplings of…

High Energy Physics - Phenomenology · Physics 2015-06-25 Johannes Blümlein , Edward Boos , Alexander Pukhov

The most celebrated aspects of precision physics are briefly summarized. New ideas are also introduced that may lead to further developments in the field of radiative corrections, with special emphasis to multi-loop numerical evaluation and…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Passarino

It has been shown in the past that the real part of the e'/e ratio is particularly sensitive to anomalous gauge couplings that modify the Standard Model Lagrangian. Due to the loose bounds on these couplings coming from low energy processes…

High Energy Physics - Phenomenology · Physics 2009-10-31 Francesco Terranova

We present a combined analysis of LHC Higgs data (signal strengths) together with LEP-2 WW production measurements. To characterize possible deviations from the Standard Model (SM) predictions, we employ the framework of an Effective Field…

High Energy Physics - Phenomenology · Physics 2016-01-13 Adam Falkowski , Martin Gonzalez-Alonso , Admir Greljo , David Marzocca

A short summary is made of several searches for new physics performed at the highest LEP2 energies.

High Energy Physics - Experiment · Physics 2017-08-23 S. Braibant , G. Giacomelli , M. Hauschild

The program TOPAZ0 was developed for computing a variety of physical observables which are related to the e+e- annihilation into fermion pairs and to the large angle Bhabha scattering around the Z resonance. Among them, the Z parameters or…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Montagna , O. Nicrosini , G. Passarino , F. Piccinini