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Related papers: Top quark pair asymmetries

200 papers

We study pair production of scalar top quarks in polarized photon-photon collisions with the subsequent decay of the top squarks into b-quarks and charginos. We simulate this process by using PYTHIA6.4 for an electron beam energy 2E_beam…

High Energy Physics - Phenomenology · Physics 2010-11-02 A. Bartl , W. Majerotto , K. Mönig , A. N. Skachkova , N. B. Skachkov

We present a calculation of heavy-flavor production in hadronic collisions in association with one jet matched to parton shower Monte Carlo programs at next-to-leading order in perturbative QCD. Top-quark decays are included and spin…

High Energy Physics - Phenomenology · Physics 2015-05-30 Simone Alioli , Sven-Olaf Moch , Peter Uwer

We present an analysis of the forward-backward asymmetry in the production of top quark pairs at the Tevatron collider. We use novel Monte Carlo methods for merging matrix elements and parton showers to combine NLO QCD predictions for tt…

High Energy Physics - Phenomenology · Physics 2013-08-09 Stefan Hoeche , Junwu Huang , Gionata Luisoni , Marek Schoenherr , Jan Winter

The order $\alpha_s^2 \alpha$ mixed QCD and weak corrections to top quark pair production by quark antiquark annihilation are computed, keeping the full dependence on the $t$ and $\bar t$ spins. We determine the contributions to the cross…

High Energy Physics - Phenomenology · Physics 2009-11-11 W. Bernreuther , M. Fuecker , Z. G. Si

We discuss top-quark pair production at hadron colliders and review available calculations of differential top-pair production cross section in perturbative QCD at approximate next-to-next-to-leading order (NNLO) within the threshold…

High Energy Physics - Phenomenology · Physics 2013-08-08 Marco Guzzi , Katerina Lipka , Sven-Olaf Moch

A measurement of the charge asymmetry in top-quark pair ($t\bar{t}$) production in association with a photon is presented. The measurement is performed in the single-lepton $t\bar{t}$ decay channel using proton-proton collision data…

High Energy Physics - Experiment · Physics 2023-07-10 The ATLAS Collaboration

The multi-purpose experiments at CERN's Large Hadron Collider have a very rich programme in top quark physics. The large amount of data allows for measuring the top quark properties with an unprecedented precision. This document presents…

High Energy Physics - Experiment · Physics 2018-12-17 Petra Van Mulders

Top quark pair production at proton-antiproton colliders is known to exhibit a forward-backward asymmetry due to higher-order QCD effects. We explore how this asymmetry might be studied at the Fermilab Tevatron, including how the asymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-18 M. T. Bowen , S. D. Ellis , D. Rainwater

We study the theoretical uncertainties in the determination of the top-quark mass using next-to-leading-order (NLO) generators, that describe the top-quark decay at different levels of accuracy, interfaced to parton showers (PS).…

High Energy Physics - Phenomenology · Physics 2018-08-29 Silvia Ferrario Ravasio , Tomáš Ježo

Recent measurements dedicated to improving the understanding of modelling top quark pair (${\text{t}\overline{\text{t}}}$) production at the LHC are summarised. These measurements, performed with proton-proton collision data collected by…

High Energy Physics - Experiment · Physics 2019-01-17 Emyr Clement

We consider, at order $\alpha_s^2$ in the QCD coupling, top-quark pair production in the continuum at various center-of-mass energies and $b$-quark pair production at the $Z$ resonance by (un)polarized electron and positron beams. For top…

High Energy Physics - Phenomenology · Physics 2023-05-22 Werner Bernreuther , Long Chen , Peng-Cheng Lu , Zong-Guo Si

Top quark pair production is presented at a polarized Muon Collider above the threshold region. The off-diagonal spin basis is the natural basis for this discussion as the top quark pairs are produced in an essentially unique spin…

High Energy Physics - Phenomenology · Physics 2009-10-31 Stephen Parke

We discuss various aspects of inclusive top-quark pair production based on TOPIXS, a new, flexible program that computes the production cross section at the Tevatron and LHC at next-to-next-to-leading logarithmic accuracy in soft and…

High Energy Physics - Phenomenology · Physics 2012-08-09 M. Beneke , P. Falgari , S. Klein , J. Piclum , C. Schwinn , M. Ubiali , F. Yan

Measurements involving top quarks provide important tests of QCD. A selected set of top quark measurements in CMS including the strong coupling constant, top quark pole mass, constraints on parton distribution functions, top quark pair…

High Energy Physics - Experiment · Physics 2019-08-13 Efe Yazgan

We revisit the possibility that the top quark forward-backward asymmetry arises from the on-shell production and decay of scalar top partners to top-antitop pairs with missing transverse energy. Although the asymmetry is produced by…

High Energy Physics - Phenomenology · Physics 2013-11-22 Abhishek Kumar , John N. Ng , Andrew Spray , Peter T. Winslow

We describe the latest results obtained by the CMS Collaboration on top quark spin and polarization properties. The top quark spin asymmetry is measured both targeting single-top quark production in the $t$-channel and single-top quark…

High Energy Physics - Experiment · Physics 2022-11-24 Fabio Iemmi

We make use of recent results in effective theory and higher-order perturbative calculations to improve the theoretical predictions of the QCD contribution to the top-quark pair production forward-backward asymmetry at the Tevatron. In…

High Energy Physics - Phenomenology · Physics 2013-05-29 Valentin Ahrens , Andrea Ferroglia , Matthias Neubert , Ben D. Pecjak , Li Lin Yang

We propose to measure the threshold lepton asymmetry, that is the forward-backward asymmetry of the charged lepton in ttbar events near the production threshold. At threshold top quark pairs are produced in an s-wave. Angular momentum…

High Energy Physics - Phenomenology · Physics 2013-03-14 Adam Falkowski , Gilad Perez , Martin Schmaltz

We present a new Monte Carlo code for Higgs boson pair production at next-to-leading order in the POWHEG-BOX Monte Carlo approach. The code is based on analytic results for the two loop virtual corrections which include the full top quark…

High Energy Physics - Phenomenology · Physics 2023-09-20 Emanuele Bagnaschi , Giuseppe Degrassi , Ramona Gröber

We study azimuthal asymmetries in heavy quark pair production in unpolarized electron-proton and proton-proton collisions, where the asymmetries originate from the linear polarization of gluons inside unpolarized hadrons. We provide cross…

High Energy Physics - Phenomenology · Physics 2015-06-16 Cristian Pisano , Daniel Boer , Stanley J. Brodsky , Maarten G. A. Buffing , Piet J. Mulders