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Related papers: Multi-parameter fits to the t-tbar threshold obser…

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We examine how accurately the general HZV couplings, with V=Z,gamma, may be determined by studying e^+e^- --> Hff-bar processes at future e^+e^- linear colliders. By using the optimal-observable method, which makes use of all available…

High Energy Physics - Phenomenology · Physics 2016-09-06 K. Hagiwara , S. Ishihara , J. Kamoshita , B. A. Kniehl

The role of the top quark in completing the Standard Model quark sector is reviewed, along with a discussion of production, decay, and theoretical restrictions on the top quark properties. Particular attention is paid to the top quark as a…

High Energy Physics - Phenomenology · Physics 2009-09-29 S. Dawson

A measurement of the Higgs boson Yukawa coupling to the top quark is presented using proton-proton collision data at $\sqrt{s} =$ 13 TeV, corresponding to an integrated luminosity of 137 fb$^{-1}$, recorded with the CMS detector. The…

High Energy Physics - Experiment · Physics 2020-12-02 CMS Collaboration

In the cosmological context, for the Standard Model to be valid up to the scale of inflation, the top quark Yukawa coupling $y_t$ should not exceed the critical value $y_t^{crit}$, coinciding with good precision (about 0.02%) with the…

High Energy Physics - Phenomenology · Physics 2015-04-30 Fedor Bezrukov , Mikhail Shaposhnikov

A simulation of top quark mass measurement scheme near the $t\bar{t}$ production threshold in future $e^{+}e^{-}$ colliders, e.g. the Circular Electron Positron Collider(CEPC), is performed. $\chi^2$ fitting method is adopted to determine…

High Energy Physics - Phenomenology · Physics 2018-05-23 Wei-Guo Chen , Xia Wan , You-Kai Wang

The strength of the Yukawa coupling of the leptons and quarks with the Higgs boson is uniquely determined by the Higgs mechanism for generating masses in the Standard Model. The top-Higgs coupling can be measured directly in the process…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Dittmaier , M. Krämer , Y. Liao , M. Spira , P. M. Zerwas

The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured…

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

We study the signal and background for the process tth, h->WW at the LHC and a 100 TeV VLHC. Signals are studied in two-, three-, and four-lepton final states. We find a statistical uncertainty in the top-quark Yukawa coupling at the LHC of…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Maltoni , D. Rainwater , S. Willenbrock

If supersymmetry (SUSY) is realized at the electroweak scale, its underlying structure and breaking mechanism may be explored with great precision by a future linear $e^+ e^-$ collider (LC) with a clean environment, tunable collision…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Y. Choi

A precise measurement of the top quark Yukawa coupling is of great importance, since it may shed light on the mechanism of EWSB. We study the prospects of such measurement during the first phase of the ILC at sqrt(s)=500 GeV, focusing in…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Juste

The measurement of Standard Model processes tests the validity of the model at a given scale and is simultaneously sensitive to new physics through loop effects or interference with the Standard Model amplitudes. A variety of studies has…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Moenig

The sensitivity of optimal integrated observables to electroweak triple gauge couplings is investigated for the process e-e+ -> W-W+ -> 4 fermions at future linear colliders. By a suitable reparameterisation of the couplings we achieve that…

High Energy Physics - Phenomenology · Physics 2011-09-13 Markus Diehl , Otto Nachtmann , Felix Nagel

Usual analyses based on scans of the seesaw parameter-space can be biassed since they do not cover in a fair way the complete parameter-space. More precisely, we show that in the common "R-parametrization", many acceptable R-matrices,…

High Energy Physics - Phenomenology · Physics 2011-03-14 J. Alberto Casas , Jesus M. Moreno , Nuria Rius , Roberto Ruiz de Austri , Bryan Zaldivar

Over the past years, the interpretation of measurements in the context of effective field theories has attracted much attention in the field of particle physics. We present a tool for interpreting sets of measurements in such models using a…

High Energy Physics - Experiment · Physics 2016-08-24 Nuno Castro , Johannes Erdmann , Cornelius Grunwald , Kevin Kröninger , Nils-Arne Rosien

If supersymmetry is discovered at the LHC, the measured spectrum of superpartner masses and couplings will allow us to probe the origins of supersymmetry breaking. However, to connect the collider-scale Lagrangian soft parameters to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gordon L. Kane , Piyush Kumar , David E. Morrissey , Manuel Toharia

A dedicated run of a future electron-positron collider (FCC-ee) at a center-of-mass energy equal to the Higgs boson mass would enable a direct measurement of the electron Yukawa coupling. However, it poses substantial experimental…

High Energy Physics - Phenomenology · Physics 2025-03-04 Barbara Anna Erdelyi , Ramona Gröber , Nudzeim Selimovic

The FCC-ee offers powerful opportunities for direct or indirect evidence for physics beyond the Standard Model, via a combination of high precision measurements and searches for forbidden and rare processes and feebly coupled particles. A…

High Energy Physics - Experiment · Physics 2021-08-23 Juan Alcaraz Maestre , Alain Blondel , Mogens Dam , Patrick Janot

We calculate limits on the trilinear soft-breaking parameter, $A_{t}$, in the Minimal Supersymmetric Standard model by requiring the absence of nonzero top squark vacuum expectation values. Assuming a low $\tan\beta$, which implies a large…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrew Bordner

A precise knowledge of charged Triple Gauge Couplings (cTGCs) is important for the determination of Higgs couplings and for constraining physics beyond the Standard Model. Future high-energy $e^{+}e^{-}$ colliders could have a significantly…

High Energy Physics - Experiment · Physics 2020-02-10 Jakob Beyer , Robert Karl , Jenny List

Suppressing naturalness concerns, we discuss the compatibility requirements of high-scale supersymmetry breaking with the Higgs boson mass constraint and gauge coupling unification. We find that to accommodate superpartner masses…

High Energy Physics - Phenomenology · Physics 2017-09-27 Sebastian A. R. Ellis , James D. Wells