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Related papers: Top Quark Spin Polarization in ep Collision

200 papers

We study the charged Higgs production at LHC via its associated production with top quark. The kinematic cuts are optimized to suppress the background processes so that the reconstruction of the charged Higgs and top quark is possible. The…

High Energy Physics - Phenomenology · Physics 2013-03-14 Xue Gong , Zong-Guo Si , Shuo Yang , Ya-juan Zheng

We derive a simple analytic expression for q \bar{q}, g g -> t \bar{t} -> b W^+ \bar{b} W^- -> b \bar{l} \nu_l \bar{b} l' \bar{\nu_{l'}} for on shell intermediate states with the interference effects due to the polarizations of the t and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Darwin Chang , Shih-Chang Lee , Paul Turcotte

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

At future $\gamma \gamma$ colliders copious production of $t \bar{t}$ pairs is possible. This would allow a detailed investigation of the interactions involving the top quark. We propose some orrelations which are sensitive to $t \bar{t}$…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Bernreuther , J. P. Ma , B. H. J. McKellar

We present the results of an O(alpha_s) calculation of the transverse polarization of top quarks produced in e+e- annihilation. In a first step we determine the transverse polarization of the top with regard to the hadron plane spanned by…

High Energy Physics - Phenomenology · Physics 2011-02-09 S. Groote , J. G. Körner

The process of top quark pair production at the ILC with subsequent decays of one of the top quarks to a charged Higgs boson and b-quark is considered. The charged Higgs decays to tau leptons whose polarization is the opposite to those…

High Energy Physics - Phenomenology · Physics 2009-10-07 E. Boos , V. Bunichev , M. Carena , C. E. M. Wagner

We present a measurement of top quark polarization in $t\bar{t}$ pair production in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV using data corresponding to 9.7 fb$^{-1}$ of integrated luminosity recorded with the D0 detector at the…

High Energy Physics - Experiment · Physics 2019-08-14 Kamil Augsten

Beam polarization at e^+e^- linear colliders will be a powerful tool for high precision analyses. In this paper we summarize the polarization-related results for Higgs and electroweak physics, QCD, Supersymmetry and alternative theories…

High Energy Physics - Phenomenology · Physics 2011-01-13 Gudrid Moortgat--Pick

Quantum tomography in high-energy physics processes has usually been restricted to the spin degrees of freedom. We address the case of top quark decays $t \to W b$, in which the orbital angular momentum ($L$) and the spins of $W$ and $b$…

High Energy Physics - Phenomenology · Physics 2024-07-12 J. A. Aguilar-Saavedra

We consider the production of tau pairs by electron-positron colliding beams at the maximum cross section near the threshold. At this energy tau pairs are produced mostly in the s-wave which implies that the spin of the tau pairs are almost…

High Energy Physics - Phenomenology · Physics 2009-12-30 Yung Su Tsai

A polarized $ep/eA$ collider (Electron--Ion Collider, or EIC), with polarized proton and light-ion beams and unpolarized heavy-ion beams with a variable center--of--mass energy $\sqrt{s} \sim 20$ to $\sim100$~GeV (upgradable to $\sim 150$…

The polarizations of the heavy quark ($q=t$ or $b$) in the process $e^+e^- \to q \bar q h$ have been calculated in the general two Higgs doublet model. The CP violating normal polarization of the top quark can reach 8%, and $2 \sim 3%$ for…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chao-Shang Huang , Shou-hua Zhu

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

In supersymmetric models, scalar top quarks, or stops, generically have parity-violating couplings to top quarks. As a result, tops produced in stop decays should be polarized. In this paper, we will argue that this effect may be observable…

High Energy Physics - Phenomenology · Physics 2009-04-03 Maxim Perelstein , Andreas Weiler

A method for the generation of ultrarelativistic electron beams with high spin polarization is put forward, where a tightly-focused linearly-polarized ultraintense laser pulse interacts with a nonprepolarized transverse-size-tailored solid…

Plasma Physics · Physics 2024-06-11 Xiaofei Shen , Zheng Gong , Karen Z. Hatsagortsyan , Christoph H. Keitel

We measure the correlation between the spin of the top quark and the spin of the anti-top quark in (ttbar -> W+ W- b bbar -> l+ nu b l- nubar bbar) final states produced in ppbar collisions at a center of mass energy sqrt(s)=1.96 TeV, where…

High Energy Physics - Experiment · Physics 2011-07-26 D0 Collaboration , V. Abazov et al.

Top-antitop quark pairs produced at the Tevatron have a sizeable spin correlation. That correlation feeds into the angular distribution of the decay products, particularly in the dilepton channel. Including the expected correlation in an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gary R. Goldstein

A calculation of the total cross section for top quark production in hadron-hadron collisions is presented based on an all-orders perturbative resummation of initial-state gluon radiative contributions to the basic quantum chromodynamics…

High Energy Physics - Phenomenology · Physics 2008-02-03 Edmond L. Berger , Harry Contopanagos

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

Spin correlations of top quarks produced in hadron collisions have not been observed experimentally with large significance. In this Letter, we propose a new variable that may enable demonstration of the existence of spin correlations with…

High Energy Physics - Phenomenology · Physics 2015-03-19 Kirill Melnikov , Markus Schulze