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Related papers: O(\alpha_s) Corrections to Longitudinal Spin-Spin …

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We provide analytical results for the $O(\alpha_s)$ corrections to the polar angle dependence of the longitudinal spin-spin correlation asymmetry in $e^+e^-\to q\bar q$. For top quark pair production the $O(\alpha_s)$ corrections to the…

High Energy Physics - Phenomenology · Physics 2014-03-13 S. Groote , J. G. Körner , J. A. Leyva

We present the full O(alpha_s) longitudinal spin-spin correlations for heavy-quark pair production at e+ e- high-energy colliders in closed analytical form. In such reactions, quark and antiquark have strongly correlated spins, and the…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. M. Tung , J. Bernabeu , J. Penarrocha

We discuss O(alpha_s) spin effects in e+ e- -> q qbar (g) for the polarization of single quarks and for spin-spin correlations of the final state quarks. Particular attention is paid to residual mass effects in the limit m_q -> 0 which are…

High Energy Physics - Phenomenology · Physics 2009-10-29 S. Groote , J. G. Körner

Using a Generic spin basis, we present a general formalism of one-loop radiative corrections to the spin correlations in the top quark pair production at the Next Linear Collider, and calculate the O(\alpha_s) QCD corrections under the soft…

High Energy Physics - Phenomenology · Physics 2011-03-23 Hong Xuan Liu , Chong Sheng Li , Zhen Jun Xiao

In this work we investigate the NLO QCD+EW corrections to the top quark pair production and their effects on the spin correlation coefficients and asymmetries at fixed-order top quark pair production and LO decay in the dilepton channel,…

High Energy Physics - Phenomenology · Physics 2021-09-29 Rikkert Frederix , Ioannis Tsinikos , Timea Vitos

We investigate the spin correlations in top quark pair production near threshold at the $ e^- e^+ $ linear collider. Comparing with the results above the threshold region, we find that near the threshold region the off-diagonal basis, the…

High Energy Physics - Phenomenology · Physics 2018-01-17 Qing Jun Zhang , Chong Sheng Li , Jian Jun Liu , Li Gang Jin

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 discuss the resummation of the potentially large O((\beta_0\alpha_s)^n) QCD corrections to the total cross section of the process e^+e^- \to t \bar t near the threshold. In this approximation, the cross section factorization into the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Oleg Yakovlev , Alexander Yelkhovsky

In this article we evaluate mass corrections up to $O((m^2/q^2)^6)$ to the three-loop polarization function induced by an axial-vector current. Special emphasis is put on the evaluation of the singlet diagram which is absent in the vector…

High Energy Physics - Phenomenology · Physics 2011-09-13 R. Harlander , M. Steinhauser

We provide analytical results for the $O(\alpha_s)$ corrections to the double-spin density matrix elements in the reaction $e^+e^-\to t\bar t$. These concern the elements $ll$, $lt$, $ln$, $tt$, $tn$, and $nn$ of the double-spin density…

High Energy Physics - Phenomenology · Physics 2016-12-07 L. Kaldamäe , S. Groote , J. G. Körner

Large extra dimension effects on the spin configuration of the top quark pair at the $e^+ e^-\to t\bar{t}$ process are studied. It is shown that the TeV scale quantum gravity effects cause significant deviations from the Standard Model…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kang Young Lee , H. S. Song , JeongHyeon 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

We calculate the longitudinal contribution to the alignment polarization $\Pl$ of quarks produced in $e^+e^-$ annihilation. In the Standard Model, the longitudinal alignment polarization vanishes at the Born term level and thus receives its…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Groote , J. G. K"orner , M. M. Tung

We compute the supersymmetric QCD corrections to the polarization and the spin correlations of top quarks produced above threshold in e+e- collisions, taking into account arbitrary longitudinal polarization of the initial beams.

High Energy Physics - Phenomenology · Physics 2010-04-05 A. Brandenburg , M. Maniatis

Recently full O(alpha_s^2, alpha_s*beta, beta^2) corrections to the threshold total cross section for e+e- to ttbar have been calculated, and the reported corrections turned out to be unexpectedly large. We study how to reduce theoretical…

High Energy Physics - Phenomenology · Physics 2016-08-25 T. Nagano , A. Ota , Y. Sumino

It is demonstrated how perturbative O(alpha_s^2) relativistic corrections to the non-relativistic stable heavy quark-antiquark production cross section in e^+e^- annihilation based on a Coulombic QCD potential can be systematically…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. H. Hoang

The object of this thesis is to study the spin-spin correlations for top quark productions and their decay at polarized e^+e^- linear colliders. For the analyses of the spin-spin correlations in top quark production, we introduce a generic…

High Energy Physics - Phenomenology · Physics 2007-05-23 Takashi Nasuno

The massive one-loop {\it QCD} corrections to the production cross sections of We present the massive one-loop {\it QCD} corrections to the production cross sections of polarized quarks in the annihilation process $e^+e^-\to q\bar{q}(g)$…

High Energy Physics - Phenomenology · Physics 2010-01-15 Michael M. Tung

We present a new derivation of the O(alpha_s) angular distribution of the outgoing $q$-quark in the production process $e^+ e^- \to\gamma,Z\to q\,\bar{q}(g)$. In our calculation, we express the three-particle phase-space integration of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. M. Tung , J. Bernabeu , J. Penarrocha

We calculate the next-to-next-to-leading order correction to the cross section for top quark pair production in e+e- annihilation in the threshold region, resumming all O [ (alpha_s/beta)^n (alpha_s^2, beta^2, alpha_s beta) ] terms of…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kirill Melnikov , Alexander Yelkhovsky
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