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Related papers: Longitudinal top polarisation measurement and anom…

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We provide a comprehensive analysis of the power of including top quark-polarisation information to kinematically challenging $t\bar t$ resonance searches, for which ATLAS and CMS start losing sensitivity. Following the general modeling and…

High Energy Physics - Phenomenology · Physics 2017-08-02 Christoph Englert , James Ferrando , Karl Nordström

We consider, both for unpolarized and longitudinally polarized electron beams, the production of a top quark pair in e+e- collisions with subsequent semileptonic top and nonleptonic anti-top decay and vice versa and investigate optimized…

High Energy Physics - Phenomenology · Physics 2015-06-25 Werner Bernreuther , Peter Overmann

The capability of the LHC to study the electromagnetic dipole moments of the top quark is discussed. In particular, the process $pp\to p\gamma\gamma p\to pt\bar{t}p$, which is supposed to be tagged by the forward/backward detectors at the…

High Energy Physics - Phenomenology · Physics 2015-07-15 Sh. Fayazbakhsh , S. Taheri Monfared , M. Mohammadi Najafabadi

Possible anomalous (or nonstandard) top-quark interactions with the gluon and those with the W boson induced by SU(3) x SU(2) x U(1) gauge-invariant dimension-6 effective operators are studied in p p -> t tbar X -> l^+ X' (l=e or mu) at the…

High Energy Physics - Phenomenology · Physics 2014-07-15 Zenro Hioki , Kazumasa Ohkuma

Angular distribution of a secondary particle in top-quark production/decay is studied in a simple and general manner. It is shown that the distribution does not depend on any possible anomalous top-quark-decay interactions whatever the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zenro Hioki

Combined analysis of recent measured $\bs$ mixing and $B \to X_s \gamma$ decays provides constraints on the anomalous $\bar{t}sW$ couplings. We discuss the perspectives to examine the anomalous $\bar{t}sW$ couplings through CKM-suppressed $…

High Energy Physics - Phenomenology · Physics 2009-01-09 Jong Phil Lee , Kang Young Lee

Recent measurements of top-quark properties (excluding the top quark mass) at ATLAS and CMS are discussed. This includes latest updates of measurements of $t\bar{t}$ production asymmetries, spin correlations and $W$ helicity, as well as the…

High Energy Physics - Experiment · Physics 2015-10-19 Andreas W. Jung

Measuring the top quark mass in its semileptonic decay mode, $t ->be^+\nu$ ($b -> \mu^- + X$), through the mass distribution of the $e^+$--$\mu^-$ pair has been shown to provide a good measurement of the top quark mass with an uncertainty…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. A. Ladinsky

Accounting for transverse momenta of the quarks, a longitudinal quark spin asymmetry exists in a transversely polarized nucleon target. The relevant leading quark distribution $g_{1T}(x,k_T^2)$ can be measured in the semi-inclusive…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. M. Kotzinian , P. J. Mulders

We investigate the effects of anomalous neutral triple gauge couplings in $ZZ$ and $Z\gamma$ production processes, followed by the leptonic decay of the $Z$ boson, at a lepton collider with center-of-mass energy $\sqrt{s}=250$~GeV and…

High Energy Physics - Phenomenology · Physics 2023-12-27 Amir Subba , Ritesh K. Singh

Measurements of the top quark by the ATLAS and CMS experiments go beyond testing the Standard Model (SM) with high precision. Axion-like particles (ALPs), a potential SM extension involving new pseudoscalar particles, exhibit strong…

High Energy Physics - Phenomenology · Physics 2026-02-04 Anh Vu Phan

If a TeV-scale charged gauge boson (W') is discovered at the Large Hadron Collider (LHC), it will become imperative to determine its chiral couplings to standard model (SM) fermions in order to learn about the underlying theory containing…

High Energy Physics - Phenomenology · Physics 2010-12-27 Shrihari Gopalakrishna , Tao Han , Ian Lewis , Zong-guo Si , Yu-Feng Zhou

We study two simple $CP$-violating asymmetries of leptons coming from the decay of $t$ and $\o t$ in $e^+e^- \ra \tt$, which do not need the full reconstruction of the $t$ or $\o t$ for their measurement. They can arise when the top quark…

High Energy Physics - Phenomenology · Physics 2009-10-28 P. Poulose , Saurabh D. Rindani

Standard Model $t\bar t$ samples in ATLAS and CMS provide an opportunity to conduct measurements of the polarization of quarks produced in top-quark decays. The bottom quarks from the $t \to W^+ b$ decays, as well as the charm, strange, up…

High Energy Physics - Phenomenology · Physics 2016-03-24 Yevgeny Kats

A large forward-backward asymmetry is seen in both the top quark rapidity distribution $A_{FB}^t$ and in the rapidity distribution of charged leptons $A_{FB}^\ell$ from top quarks produced at the Tevatron. We study the kinematic and dynamic…

High Energy Physics - Phenomenology · Physics 2012-02-15 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Jiang-Hao Yu , Hao Zhang

We perform a comparative study of the reach of future $e^+e^-$ collider options for the scale of non-resonant new physics effects in the top quark sector, phrased in the language of higher-dimensional operators. Our focus is on the…

High Energy Physics - Phenomenology · Physics 2017-10-26 Christoph Englert , Michael Russell

In the $pp \rightarrow t\bar{t}$ process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a…

High Energy Physics - Experiment · Physics 2016-11-21 ATLAS Collaboration

Compact analytic expressions have been obtained for the first order perturbative QCD corrections to the inclusive spectra of the leptons in the semileptonic decays of polarised heavy quarks. Charmed and beautiful $\Lambda$ baryons from…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marek Jezabek

Highlights of measurements of the properties of the top quark at the LHC are presented. The measurements probe a range of the properties of the top quark, including the structure of the $Wtb$ vertex, the top-Z coupling and the top-quark…

High Energy Physics - Experiment · Physics 2017-05-26 Mark Owen

The weak decay of a polarized top quark has a rich structure of angular correlations among its decay products. We describe some of the noteworthy features of such decays. We then examine the three modes of single top production, with an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gregory Mahlon