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Related papers: Extracting alpha_s from Electron-Positron Annihila…

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The inclusive cross-section for jet production in association with a Z boson decaying into an electron-positron pair is measured as a function of the transverse momentum and the absolute rapidity of jets using 19.9 fb$^{-1}$ of $\sqrt s =…

High Energy Physics - Experiment · Physics 2019-11-05 ATLAS Collaboration

We calculate total hadron-hadron cross sections at high energies using the Low-Nussinov two-gluon model of the Pomeron. The gluon exchange is represented by a phenomenological potential including screened color-Coulomb, screened confining,…

Nuclear Theory · Physics 2009-11-10 Wei-Ning Zhang , Cheuk-Yin Wong

Determinations of alpha_s are reviewed. Current results are limited to a precision of around 3-20%, largely by theoretical uncertainties. All measurements are consistent with a `world average' value of 0.118 +- 0.005 and there is no…

High Energy Physics - Experiment · Physics 2011-07-19 P. N. Burrows

We describe a new method for obtaining the CP phase alpha via measurements of B_{d,s} -> K(*) Kbar(*) decays. This method is particularly appropriate for hadron colliders since some of the branching ratios are small [O(10^{-6})], and since…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alakabha Datta , David London

Recently published results from the PAMELA experiment have shown conclusive evidence for an excess of positrons at high (~ 10 - 100 GeV) energies, confirming earlier indications from HEAT and AMS-01. Such a signal is generally expected from…

Astrophysics · Physics 2009-12-15 Ilias Cholis , Douglas P. Finkbeiner , Lisa Goodenough , Neal Weiner

The C-parameter event-shape distribution for e+e- annihilation into hadrons is computed in the framework of SCET including input from fixed-order perturbation theory. We calculate all missing ingredients for achieving N3LL resummation…

High Energy Physics - Phenomenology · Physics 2016-02-17 Andre H. Hoang , Daniel W. Kolodrubetz , Vicent Mateu , Iain W. Stewart

Rates of the two-, three-, four- and five-photon annihilations of the electron-positron pairs are determined numerically for the three-body positronium ion Ps$^-$ ($e^- e^+ e^-$) and four-body bi-positronium `molecule' Ps$_2$ ($e^- e^+ e^-…

High Energy Physics - Phenomenology · Physics 2015-05-13 Alexei M. Frolov

An analysis procedure is proposed to measure the antiquark distributions in the proton over the region 0.01 < x < 0.1. The procedure involves the measurement of high p_t asymmetric direct photon and jet final states in pp interactions. This…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. G. Badalian , S. Heppelmann

The Born cross section and dressed cross section of $e^+e^-$ to $b\bar{b}$ and the total hadronic cross section in $e^+e^-$ annihilation in the bottomonium energy region are calculated based on the Rb values measured by the BaBar and Belle…

High Energy Physics - Phenomenology · Physics 2021-02-24 Xiang-Kun Dong , Xiao-Hu Mo , Ping Wang , Chang-Zheng Yuan

We update our extraction of parton-to-charged hadron fragmentation functions at next-to-leading order accuracy in QCD, focusing on the wealth of data collected at the Large Hadron Collider over the past decade. We obtain an accurate…

High Energy Physics - Phenomenology · Physics 2023-11-30 Ignacio Borsa , Daniel de Florian , Rodolfo Sassot , Marco Stratmann

Hadron elementary particle measurements have long revealed an alpha-dependence in the long-lived threshold-state lifetimes, together with an alpha-related mass structure, where alpha ~ 1/137 is the fine structure constant. A detailed…

High Energy Physics - Phenomenology · Physics 2009-11-11 Malcolm H. Mac Gregor

Process of electron-positron annihilation into $\eta(\eta')2\pi$ is described within the extended NJL model in the energy range up to about 2 GeV. Contributions of intermediate vector mesons $\rho(770)$ and $\rho(1450)$ are taken into…

High Energy Physics - Phenomenology · Physics 2014-01-15 M. K. Volkov , A. B. Arbuzov , D. G. Kostunin

The forward-backward asymmetry is an important measurable quantity which can enable independent determination of the neutral-current couplings of fermions. In this paper, we extend the definition of the asymmetry from the partonic level to…

High Energy Physics - Phenomenology · Physics 2023-03-22 W. Yang , C. Li

The reactions of electron-positron to nucleon-antinucleon pair at energy threshold are studied in a non-perturbative quark model. The puzzling experimental result that the ratio of the cross section of electron-positron to proton-antiproton…

High Energy Physics - Phenomenology · Physics 2009-07-03 Y. Yan , K. Khosonthongkee , C. Kobdaj , P. Suebka

We reevaluate the dispersion integrals of the leading order hadronic contributions to the running of the QED fine structure constant alpha(s) at s=M_Z^2, and to the anomalous magnetic moments of the muon and the electron. Finite-energy QCD…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Davier , A. Hocker

An electron-positron linear collider in the energy range between 500 and 1000 GeV is of crucial importance to precisely test the Standard Model and to explore the physics beyond it. The physics program is complementary to that of the Large…

High Energy Physics - Experiment · Physics 2009-11-07 R. -D. Heuer

The b-hadron production cross section is measured with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV, using 3.3 pb^-1 of integrated luminosity, collected during the 2010 LHC run. The b-hadrons are selected by partially…

High Energy Physics - Experiment · Physics 2012-08-27 ATLAS Collaboration

I survey a number of interesting tests of quantum chromodynamics at the amplitude level which can be carried out in electron-positron annihilation and in photon-photon collisions at low energy, including measurements of fundamental…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky

We analyse pp elastic scattering data at the highest accelerator energy region (between 10 and 63 GeV) through a multiple diffraction approach. The use of Martin's formula in a model developed earlier is substituted by the introduction of a…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. F. Martini , M. J. Menon

Using recent CLEO III results for the cross section for $e^+e^- \to {\rm hadrons}$ at seven centre-of-mass energies between 6.964 and 10.538 GeV, we derive a value for the strong coupling constant…

High Energy Physics - Phenomenology · Physics 2008-11-26 Johann H. Kuhn , Matthias Steinhauser , Thomas Teubner