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Related papers: A New Twist on Top Quark Spin Correlations

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We study the production cross section of the $t$-channel single top quark at the LHC in the noncommutative space-time. It is shown that the deviation of the $t$-channel single top cross section from the Standard Model value because of…

High Energy Physics - Phenomenology · Physics 2015-01-27 Seyed Yaser Ayazi , Sina Esmaeili , Mojtaba Mohammadi Najafabadi

We investigate a number of observables that are and will be instrumental in the exploration of $\tbart$ production and decay at the Tevatron and the LHC. For this analysis we made a computer program that incorporates besides the NLO QCD…

High Energy Physics - Phenomenology · Physics 2014-11-20 Werner Bernreuther , Zong-Guo Si

Extensions of the Standard Model often predict new chiral interactions for top quark, which will contribute to top quark spin correlation and polarization in $t\bar{t}$ production at the LHC. In this work, under the constraints from the…

High Energy Physics - Phenomenology · Physics 2015-03-17 Junjie Cao , Lei Wu , Jin Min Yang

Spin correlations in the production of top-antitop quark ($t\bar{t}$) pairs at the Large Hadron Collider (LHC) are an experimentally verified prediction of the Standard Model. In this paper, we compute the full spin density matrix for…

High Energy Physics - Phenomenology · Physics 2021-09-17 Baptiste Ravina , Ethan Simpson , James Howarth

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

Recent measurements of the correlation between the spin of the top and the spin of the anti-top quark produced in proton anti-proton scattering at a centre of mass energy of 1.96 TeV by the CDF and D0 collaborations are discussed. Using up…

High Energy Physics - Experiment · Physics 2022-03-02 Tim Head

Precise measurements of the properties of the top quark test the Standard Model (SM) and can be used to constrain new physics models. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the SM,…

High Energy Physics - Experiment · Physics 2016-07-08 Mohammad J. Kareem

We compare theoretical expectations for the observation of spin correlations in top quark pair production and decay at the Fermilab Tevatron and the CERN Large Hadron Collider (LHC). In particular, we note that the differing top quark pair…

High Energy Physics - Phenomenology · Physics 2022-03-02 Gregory Mahlon

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 discuss top quark production and its subsequent decay at lepton colliders including both QCD corrections and anomalous gamma / Z - t t-bar couplings. The off-diagonal spin basis for the top and anti-top quarks is shown to be useful to…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Kiyo , J. Kodaira , K. Morii , T. Nasuno , S. Parke

We describe the off-diagonal spin basis for observing angular correlations in top quark pair production events at the Fermilab Tevatron. For events initiated by quark-antiquark annihilation, the top and antitop quark spins are 100%…

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

Top quark pair production at photon-photon colliders is studied in low scale quantum gravity scenario. From the dependence of the cross sections on the spin configuration of the top quark and anti-quark, we introduce a new observable, top…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kang Young Lee , Seong Chan Park , H. S. Song , Jeonhyeon Song , Chaehyun Yu

Spin correlations, using a generic spin basis, are investigated to leading order in QCD for top quark production at lepton colliders. Even though, these radiative corrections induce an anomalous gamma/Z magnetic moment for the top quarks…

High Energy Physics - Phenomenology · Physics 2010-02-03 Jiro Kodaira , Takashi Nasuno , Stephen Parke

A comparison is made between the off-diagonal and helicity spin bases for top quark pair production at the FNAL Tevatron. In the off-diagonal basis, 92% of the top quark pairs are in the spin configuration up-down plus down-up, whereas in…

High Energy Physics - Phenomenology · Physics 2016-09-06 Gregory Mahlon , Stephen Parke

We propose to observe the top spin correlation effect at Tevatron through the measurement of the correlated asymmetries of the charged lepton momenta using the dilepton decay events of top and anti-top quark pairs. The possibility of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Darwin Chang , Shih-Chang Lee , Alexei Soumarokov

An analysis of the spin correlation effects in top quark pair production at hadron colliders is presented with special emphasis for the Large Hadron Collider (LHC). At the LHC top quark pair production is dominated by gluon-gluon fusion.…

High Energy Physics - Phenomenology · Physics 2010-05-04 Stephen J. Parke

Measurements of spin correlation in top quark pair production are presented using data collected with the ATLAS detector at the LHC with proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity…

High Energy Physics - Experiment · Physics 2015-01-27 ATLAS Collaboration

A measurement of spin correlation in ttbar production is reported using data collected with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 2.1 fb^-1. Candidate events are selected in the dilepton topology with…

High Energy Physics - Experiment · Physics 2015-03-20 ATLAS Collaboration

Top quark pairs are produced with strongly correlated spins in the partonic reactions $q\bar{q}\to t\bar{t}$ and $gg\to t\bar{t}$. A complete description of these effects in terms of the spin density matrix of the $t\bar{t}$ system in…

High Energy Physics - Phenomenology · Physics 2009-10-28 Arnd Brandenburg

Spin correlations between top-quark and anti-top-quark in pair production are sensitive to physics beyond the standard model. A complete set of observables, that can be used to measure all independent parameters of the production spin…

High Energy Physics - Phenomenology · Physics 2017-10-11 Kai Ma