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

200 papers

We study the longitudinal polarization of hyperons and anti-hyperons at forward pseudorapidity, $2.5<\eta<4$, in singly polarized $pp$ collisions at RHIC energies by using different parameterizations of the polarized parton densities and…

High Energy Physics - Phenomenology · Physics 2010-04-06 Wei Zhou , Shan-shan Zhou , Qing-hua Xu

Interference effects in effective field theory (EFT) analyses can significantly distort sensitivity expectations, leaving subtle yet distinct signatures in the reconstruction of final states crucial for limit setting around Standard Model…

High Energy Physics - Phenomenology · Physics 2025-03-26 Felix Egle , Christoph Englert , Margarete Mühlleitner , Michael Spannowsky

We consider top-antitop quark ($t{\bar t}$) production at the Large Hadron Collider (LHC) with subsequent decay into dileptonic and lepton plus jets final states. We present a set of leptonic angular correlations and distributions with…

High Energy Physics - Phenomenology · Physics 2016-01-27 Werner Bernreuther , Dennis Heisler , Zong-Guo Si

A systematic investigation of the nuclear-polarization effects in one- and few-electron heavy ions is presented. The nuclear-polarization corrections in the zeroth and first orders in $1/Z$ are evaluated to the binding energies, the…

Atomic Physics · Physics 2015-04-23 Andrey V. Volotka , Günter Plunien

We analyze the LHC prospects for measurements of the $t\bar{t}$ pair produced exclusively in photon-photon or semi-exclusively in photon-Pomeron and Pomeron-Pomeron processes using protons tagged in forward proton detectors on both sides of…

High Energy Physics - Phenomenology · Physics 2020-10-28 Victor P. Goncalves , Daniel E. Martins , Murilo S. Rangel , Marek Tasevsky

Current searches for direct production of scalar top quarks, or stops, in supersymmetry focus on their decays into W boson + b quark + neutralino by way of top + neutralino and bottom + chargino. While the polarization of the top quark…

High Energy Physics - Phenomenology · Physics 2014-04-01 Ian Low

The electroweak production in the $t$ channel is the most dominant production mode of single top quarks at the LHC. The ratio of the cross sections of the top quark and antiquark production provides an insight into the inner structure of…

High Energy Physics - Experiment · Physics 2019-01-17 Denise Mueller

We present theoretical results at approximate NNLO in QCD for top-quark pair-production total cross sections and top-quark differential distributions at the LHC in the SMEFT. In this work we consider effects of new physics parametrized by…

High Energy Physics - Phenomenology · Physics 2024-10-01 Alberto Tonero , Nikolaos Kidonakis

The polarization of a top quark can be sensitive to new physics beyond the standard model. Since the charged lepton from top quark decay is maximally correlated with the top quark spin, it is common to measure the polarization from the…

High Energy Physics - Phenomenology · Physics 2013-05-30 Edmond L. Berger , Qing-Hong Cao , Jiang-Hao Yu , Hao Zhang

The transverse polarization observed in the inclusive production of Lambda hyperons in the high energy collisions of unpolarized hadrons is tackled by considering a new set of spin and kT dependent quark fragmentation functions. Simple…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Anselmino , D. Boer , U. D'Alesio , F. Murgia

We compute the non-factorisable ${\cal O}(\alpha_s^2)$ corrections to $t$-channel single-top quark production at the LHC. These peculiar corrections arise because of interactions between the heavy- and the light-quark lines and appear for…

High Energy Physics - Phenomenology · Physics 2022-06-29 Christian Brønnum-Hansen , Kirill Melnikov , Jérémie Quarroz , Chiara Signorile-Signorile , Chen-Yu Wang

The production of heavy flavor quark pairs, including top-anti-top, at the LHC proceeds primarily through gluon fusion. The correlation between the gluon spins affects various spin correlations between the produced quark and anti-quark.…

High Energy Physics - Phenomenology · Physics 2017-10-05 Gary R. Goldstein , S. Liuti

We explore the possibility that the right-handed top quark is composite, identifying possible signatures of compositeness and how they might manifest themselves at the LHC and Tevatron. We perform a complete analysis of the dimension six…

High Energy Physics - Phenomenology · Physics 2009-06-02 Kunal Kumar , Tim M. P. Tait , Roberto Vega-Morales

In top quark production, the polarization of top quarks, decided by the chiral structure of couplings, is likely to be modified in the presence of any new physics contribution to the production. Hence the same is a good discriminator for…

High Energy Physics - Phenomenology · Physics 2019-09-25 Rohini Godbole , Monoranjan Guchait , Charanjit K. Khosa , Jayita Lahiri , Seema Sharma , Aravind H. Vijay

We study the four-top final state at the LHC as a probe for New Physics (NP) effects due to new particles that couple predominantly to the top quark and whose masses are below the top-quark-pair production threshold. We consider simple NP…

High Energy Physics - Phenomenology · Physics 2020-01-29 Ezequiel Alvarez , Aurelio Juste , Rosa María Sandá Seoane

We argue that the enhancement in the spin polarization of anti-hyperons compared to the polarization of the hyperons in noncentral relativistic heavy-ion collisions arises as a result of an interplay between the chiral and helical vortical…

High Energy Physics - Phenomenology · Physics 2022-11-08 Victor E. Ambrus , M. N. Chernodub

We consider all relevant dimension six operators to perform a model independent analysis of flavour changing single top production at the LHC.

High Energy Physics - Phenomenology · Physics 2007-05-23 P. M. Ferreira , R. Santos

We study the polarization of particles in relativistic heavy-ion collisions at very high energy along the beam direction within a relativistic hydrodynamic framework. We show that this component of the polarization decreases much slower…

Nuclear Theory · Physics 2018-01-17 F. Becattini , Iu. Karpenko

Recently, experimental collaborations have reported $\mathcal{O}(10)$ upper limits on the signal strength of four-top production at the LHC, which already leads to competitive constraints on certain type of top-quark operators. On the other…

High Energy Physics - Phenomenology · Physics 2017-11-28 Cen Zhang

It has been realized for quite a long time that single-spin experiments, in which one of the colliding objects is transversely polarized, can be helpful in studying the properties of strong interaction in general and in testing Quantum…

High Energy Physics - Phenomenology · Physics 2009-10-31 Zuo-tang Liang , C. Boros