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Related papers: Single top polarisation as a window to new physics

200 papers

In the context of $SU(2)_L\times U(1)$ dimension six operators we study the potential of the LHeC to provide information on top quark effective interactions. We focus on single antitop production and how it is affected not only by the…

High Energy Physics - Phenomenology · Physics 2015-06-03 I. A. Sarmiento-Alvarado , Antonio O. Bouzas , F. Larios

We investigate the prospects to observe effects of transverse polarization of top quarks in $pp,p\bar{p}\to t\bar{t}X$. QCD absorptive parts generate a polarization of top quarks and antiquarks transverse to the production plane in the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Werner Bernreuther , Arnd Brandenburg , Peter Uwer

We perform a model independent analysis of the flavour changing strong interaction vertices relevant to the LHC. In particular, the contribution of dimension six operators to single top production in various production processes is…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. M. Ferreira , O. Oliveira , R. Santos

We report on a calculation of the full one-loop weak corrections through the order $\alpha_{\mathrm{S}}^2\alpha_{\mathrm{W}}$ to parton-parton scattering in all possible channels at the Relativistic Heavy Ion Collider (RHIC) running with…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Moretti , M. R. Nolten , D. A. Ross

We show that the polarization of hyperons observed in high energy collisions using unpolarized hadron beams and unpolarized nucleon or nuclear targets is closely related to the left-right asymmetries observed in single spin inclusive hadron…

High Energy Physics - Phenomenology · Physics 2007-05-23 Liang Zuo-tang

Precision measurements of high energy top quarks at the LHC constitute a powerful probe of new physics. We study the effect of four fermion operators involving two tops and two light quarks on the high energy tail of the $t\bar t$ invariant…

High Energy Physics - Phenomenology · Physics 2019-02-20 Marco Farina , Cristina Mondino , Duccio Pappadopulo , Joshua T. Ruderman

We define three orthogonal axes to investigate the top quark polarization in the $t$-channel single top process. We provide expressions for the polarization in these axes in terms of anomalous $Wtb$ couplings. It is found that the…

High Energy Physics - Phenomenology · Physics 2014-06-23 J. A. Aguilar-Saavedra , S. Amor dos Santos

We investigate the effects of top quark compositeness on various physical parameters, and obtain lower limits on the compositeness scale from electroweak precision data. We consider corrections to top quark decay rates and other physical…

High Energy Physics - Phenomenology · Physics 2009-09-11 Howard Georgi , Lev Kaplan , David Morin , Andreas Schenk

The polarisation of top quarks produced in high energy processes can be a very sensitive probe of physics beyond the Standard Model. The kinematical distributions of the decay products of the top quark can provide clean information on the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Rohini M. Godbole , Lisa Hartgring , Irene Niessen , Chris D. White

Fermion compositeness, and other types of new physics that can be described by the exchange of very massive particles, can manifest themselves as the result of an effective four-fermion contact interaction. In the case of the processes…

High Energy Physics - Phenomenology · Physics 2011-01-25 A. A. Pankov , N. Paver

We study the sensitivity of the Large Hadron Collider (LHC) to top quark chromomagnetic (CMDM) and chromoelectric (CEDM) dipole moments and $Wtb$ effective couplings in single-top production in association with a $W^-$ boson, followed by…

High Energy Physics - Phenomenology · Physics 2015-11-02 Saurabh D. Rindani , Pankaj Sharma , Anthony W. Thomas

Measuring top polarization is extremely important in understanding any new physics that couples to top quark. Here, we take up the task of extracting polarization of top quark coming from TeV-scale stop decay at the upgraded high luminosity…

High Energy Physics - Phenomenology · Physics 2021-11-30 Jayita Lahiri

Collisions of particles at the energy frontier can reveal new particles and forces via localized excesses. However, the initial observation may be consistent with a large variety of theoretical models, especially in sectors with new top…

High Energy Physics - Phenomenology · Physics 2025-02-21 Krish Wu , Brandon Sun , Nitish Polishetty , Justin Kline , Max Fieg , Daniel Whiteson

We investigate the quantum properties of heavy-fermion pairs, such as $t\bar t$ or $\tau^+\tau^-$, produced in lepton-lepton collisions with polarised beams. Focusing on spin correlations, entanglement, Bell-inequality violation, and…

High Energy Physics - Phenomenology · Physics 2026-01-28 Mohammad Mahdi Altakach , Priyanka Lamba , Fabio Maltoni , Kazuki Sakurai

The recent observations of sizable transverse fractions of B-> phi K* are strongly contrary to the Standard Model expectation. We analyze all possible new-physics four-quark operators. We find that two classes of new-physics operators could…

High Energy Physics - Phenomenology · Physics 2009-11-10 Prasanta Kumar Das , Kwei-Chou Yang

The most general set of new physics effective operators contributing to the decay of an unpolarized top quark into a bottom quark and a W gauge boson are considered at next-to-leading order in QCD. We find that the dipole operator…

High Energy Physics - Phenomenology · Physics 2012-01-31 S. Fajfer , J. Drobnak , J. F. Kamenik

We consider top quark production and decay in the narrow width approximation and study if the polarisation effects, that manifest themselves in correlations of angular distributions of particles from top quark decays and final state jets in…

High Energy Physics - Phenomenology · Physics 2024-11-25 Sergei Makarov , Kirill Melnikov , Paolo Nason , Melih A. Ozcelik

Fermion compositness, and other new physics which can be described by an exchange of very massive particles ($Z^\prime$ boson, leptoquarks, sparticles with R-parity violating couplings), can be manifest itself as the presence of a strong…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. A. Pankov

We study the sensitivity of the Large Hadron Collider (LHC) to top quark chromomagnetic (CMDM) and chromoelectric (CEDM) dipole moments and $Wtb$ effective couplings in single-top production in association with a $W^-$ boson, followed by…

High Energy Physics - Phenomenology · Physics 2015-10-29 Saurabh D. Rindani , Pankaj Sharma , Anthony W. Thomas

Transverse $\Lambda$ polarization observed over four decades ago contradicted expectations from early leading-order perturbative QCD calculations. Measurements of $\Lambda$ polarization from unpolarized $pp$ and $p$A collisions have been…

High Energy Physics - Experiment · Physics 2023-07-18 Cynthia Nunez