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Related papers: Axial Contributions at the Top Threshold

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We describe the QQbar_threshold library for computing the production cross section of heavy quark-antiquark pairs near threshold at electron-positron colliders. The prediction includes all presently known QCD, electroweak, Higgs, and…

High Energy Physics - Phenomenology · Physics 2016-11-23 M. Beneke , Y. Kiyo , A. Maier , J. Piclum

We present complete results for the $O(\alpha_s)$ corrections to the production of a heavy quark pair plus a hard photon, in $e^+ e^-$ annihilation, including both photon and $Z$ intermediate states. Virtual corrections are calculated…

High Energy Physics - Phenomenology · Physics 2009-10-28 L. Magnea , E. Maina

Heavy quarkonium production at high transverse momentum ($p_T$) in hadronic collisions is explored in the QCD factorization approach. We find that the leading power in the $1/p_T$ expansion is responsible for high $p_T$ regime, while the…

High Energy Physics - Phenomenology · Physics 2021-08-03 Kyle Lee , Jian-Wei Qiu , George Sterman , Kazuhiro Watanabe

In the framework of the nonrelativistic diquark model of the heavy baryons and the perturbative approach of QCD we predict the value and energy dependence for the total cross section of the Lambda_b- and Sigma_b^* -baryons pair production…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. A. Saleev

We present an in-depth analysis of axions and axion-like particles in top-pair production at the LHC. Our main goal is to probe the axion coupling to top quarks at high energies. To this end, we calculate the top-antitop cross section and…

High Energy Physics - Phenomenology · Physics 2024-06-10 Anh Vu Phan , Susanne Westhoff

The 1+1 dimensional massive Dirac equation is solved exactly in light-cone coordinates for $x^+ > 0$ and $x^- > -L$, in the presence of an arbitrary $x^+$ dependent electric field. Our solution resolves the ambiguity at $p^+ = 0$. We also…

High Energy Physics - Theory · Physics 2009-11-07 T. N. Tomaras , N. C. Tsamis , R. P. Woodard

This is the first in a series of papers, in which we compute the third-order QCD corrections to top-antitop production near threshold in e+ e- collisions. The present paper provides a detailed outline of the strategy of computation in the…

High Energy Physics - Phenomenology · Physics 2024-09-11 M. Beneke , Y. Kiyo , K. Schuller

We discuss electro-magnetic and weak production of pions on nucleons and show how results of experiments and their interpretation in terms of chiral quark models with explicit meson degrees of freedom combine to reveal the ground-state…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Sirca , L. Amoreira , M. Fiolhais , B. Golli

The next-to-next-to-leading order (NNLO) QCD corrections to top quark threshold pair production in gamma-gamma collisions are computed. The NNLO effects turn out to be significant. Threshold cross sections in gamma-gamma and e+e- collisions…

High Energy Physics - Phenomenology · Physics 2014-11-17 Andrzej Czarnecki , Kirill Melnikov

We present the higher order QCD corrections to the fragmentation functions and the corresponding cross sections.

High Energy Physics - Phenomenology · Physics 2007-05-23 W. L. van Neerven

We review exclusive top pair production including decays at a future high-energy lepton collider, both in the threshold region and for higher energies. For the continuum process, we take complete QCD next-to-leading order matrix elements…

We present the analytic calculation of the Master Integrals for the two-loop, non-planar topologies that enter the calculation of the amplitude for top-quark pair hadroproduction in the quark-annihilation channel. Using the method of…

High Energy Physics - Phenomenology · Physics 2019-09-04 Matteo Becchetti , Roberto Bonciani , Valerio Casconi , Andrea Ferroglia , Simone Lavacca , Andreas von Manteuffel

We study the one-loop radiative corrections to pair production of the supersymmetric scalar partners of the standard fermions in e+e- annihilation. Both electroweak and SUSY-QCD corrections are considered. Applications are for production of…

High Energy Physics - Phenomenology · Physics 2011-03-23 Abdesslam Arhrib , Wolfgang Hollik

We present an approach to predict exclusive $W^+bW^-\bar{b}$ production at lepton colliders that correctly describes the top-anti-top threshold as well as the continuum region. We incorporate $t\bar{t}$ form factors for the NLL threshold…

The production cross sections of charmonia, charmonium-bottomonium and bottomonia pairs in a single boson $e^+e^-$ annihilation have been studied in a wide range of energies, which will be achieved at future $e^+e^-$ colliders such as ILC…

High Energy Physics - Phenomenology · Physics 2023-06-19 I. N. Belov , A. V. Berezhnoy , E. A. Leshchenko

QCD corrections to the electron positron annihilation cross-section into hadrons and to the hadronic $Z$ boson decay rate are reviewed. Formal developments are introduced in a form particularly suited for practical applications. These…

High Energy Physics - Phenomenology · Physics 2009-10-28 K. G. Chetyrkin , J. H. Kühn , A. Kwiatkowski

Unlike other examples of fermion pair production in e+ e- collisions, we show that top-quark pairs are produced in an essentially unique spin configuration in polarized e+ e- colliders at all energies. Since the directions of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stephen Parke

Polarization studies for heavy quarks can lead to important tests of the Standard Model. Top quark pair production in $e^+e^-$ annihilation is considered near energy threshold. It is shown that for longitudinally polarized electrons the…

High Energy Physics - Phenomenology · Physics 2011-03-02 M. Jezabek

The production of W+ W- b bbar from e+ e- collisions at energies close to the t tbar threshold is dominated by the resonant process with a nearly on-shell t tbar intermediate state. The W b pairs in the final state can also be reached…

High Energy Physics - Phenomenology · Physics 2022-09-21 M. Beneke , B. Jantzen , P. Ruiz-Femenia

We consider an extension of the finite-temperature Dyson-Schwinger equation (DSE) approach to heavy mesons and quarkonia and apply it to calculate the cross section for the J/Psi breakup reaction J/Psi + pi --> D + D. We study the effects…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. B. Blaschke , G. R. G. Burau , M. A. Ivanov , Yu. L. Kalinovsky , P. C. Tandy