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Related papers: Direct Extraction of QCD Lambda MS-bar from e+e- J…

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We consider the QCD corrections to the electric dipole moment of the neutron in the Minimal Supersymmetric Standard Model. We provide a master formula for the Wilson coefficients at the low energy scale including for the first time the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Giuseppe Degrassi , Enrico Franco , Schedar Marchetti , Luca Silvestrini

Fragmentation of heavy quarks into heavy-flavoured hadrons receives both perturbative and non-perturbative contributions. We consider perturbative QCD corrections to heavy quark production in $e^+e^-$ collisions to next-to-next-to-leading…

High Energy Physics - Phenomenology · Physics 2024-06-12 Leonardo Bonino , Matteo Cacciari , Giovanni Stagnitto

Perturbative cross-sections in QCD are beset by logarithms of kinematic invariants, whose arguments vanish when heavy particles are produced near threshold. Contributions of this type often need to be summed to all orders in the coupling,…

High Energy Physics - Phenomenology · Physics 2020-01-08 N. Bahjat-Abbas , D. Bonocore , J. Sinninghe Damsté , E. Laenen , L. Magnea , L. Vernazza , C. D. White

In this talk we discuss an algorithm for the numerical calculation of one-loop QCD amplitudes and present results at next-to-leading order for jet observables in electron-positron annihilation calculated with the above-mentioned method. The…

High Energy Physics - Phenomenology · Physics 2011-12-16 S. Becker , D. Goetz , C. Reuschle , C. Schwan , S. Weinzierl

The QED Coulomb correction is one of the most important corrections to the e+ e- --> W+ W- total cross section near threshold. We calculate these corrections through second order, and discuss the implications for extracting M_W from a…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. S. Fadin , V. A. Khoze , A. D. Martin , W. J. Stirling

Super-leading logarithmic terms have previously been observed in non-global QCD observables. In this paper we re-calculate the first super-leading contribution to the `gaps between jets' cross-section using a diagrammatic fixed order…

High Energy Physics - Phenomenology · Physics 2010-04-21 James Keates , Michael H. Seymour

We report on studies of next-to-leading order (NLO) QCD corrections to the process $pp\rightarrow e^+\nu_e\mu^+\nu_\mu jj$ which is associated with vector-boson fusion (VBF) production of an intermediate $W^+W^+$ pair. The impact of…

High Energy Physics - Phenomenology · Physics 2013-11-07 Lucia Hosekova

Within the nonrelativistic QCD (NRQCD) factorization framework, we compute the long-awaited ${\mathcal O}(\alpha_s^2)$ correction for the exclusive double charmonium production process at $B$ factories, {\it i.e.}, $e^+e^-\to J/\psi+\eta_c$…

High Energy Physics - Phenomenology · Physics 2022-11-28 Feng Feng , Yu Jia , Zhewen Mo , Wen-Long Sang , Jia-Yue Zhang

We present the calculations of the complete next-to-leading order (NLO) QCD corrections (including supersymmetric QCD) to the inclusive total cross sections of the associated production processes $pp\to A^0Z^0+X$ in the Minimal…

High Energy Physics - Phenomenology · Physics 2009-11-11 Qiang Li , Chong Sheng Li , Jian Jun Liu , Li Gang Jin , C. -P. Yuan

We present a new calculation of the CP violation parameter $\epsilon^{\prime}/ \epsilon$. The results reported in this paper have been obtained by using the $\Delta S=1$ effective Hamiltonian computed at the next-to-leading order, including…

High Energy Physics - Phenomenology · Physics 2010-11-01 M. Ciuchini , E. Franco , G. Martinelli , L. Reina

Recently, the CMS and ATLAS Collaborations at the CERN Large Hadron Collider (LHC) have set exclusion limits on the quark compositeness scale by comparing their data to the leading order and the scaled next-to-leading order (NLO) QCD…

High Energy Physics - Phenomenology · Physics 2011-04-20 Jun Gao , Chong Sheng Li , Jian Wang , Hua Xing Zhu , C. -P. Yuan

We revisited excited leptons ($\bar{l^*}l$) production through gauge mediation only at LHC, followed by their two body decays into Standard Model (SM) particles. We include the next-to-leading order (NLO) QCD corrections to these processes.…

High Energy Physics - Phenomenology · Physics 2015-03-10 Swapan Majhi

The analysis of event shape variables enable studies of QCD and determinations of alpha-s, but require predictions to next-to-leading order. The predictions of two next-to-leading order programs are compared for current jet thrust, current…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. J. McCance

The heavy jet mass distribution in e+e- collisions is computed to next-to-next-to-next-to leading logarithmic (NNNLL) and next-to-next-to leading fixed order accuracy (NNLO). The singular terms predicted from the resummed distribution are…

High Energy Physics - Phenomenology · Physics 2010-09-09 Yang-Ting Chien , Matthew D. Schwartz

Low-energy experiments allow for some of the most precise measurements in particle physics, such as $g-2$. To make the most of these experiments, theory needs to match the experimental precision. Over the last decade, this meant that even…

High Energy Physics - Phenomenology · Physics 2023-09-13 Yannick Ulrich

We report next-to-leading order perturbative QCD predictions of 4 jet event shape variables for the process e+e- \to 4 jets obtained using the general purpose Monte Carlo EERAD2. This program is based on the known `squared' one loop matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. M. Campbell , M. A. Cullen , E. W. N. Glover

I review progress related to the calculation of QCD jet cross sections at the NLO accuracy. After a short introduction into the theory of NLO calculations, I discuss two recent developments: the calculation of two- and three-jet…

High Energy Physics - Phenomenology · Physics 2013-05-29 Zoltan Trocsanyi

We give an overview of our calculation of the next-to-next-to-leading order (NNLO) QCD corrections to W + jet production in hadronic collisions. Phenomenological results for multiple differential distributions are compared to CMS data for 8…

High Energy Physics - Phenomenology · Physics 2018-07-25 Aude Gehrmann-De Ridder , Thomas Gehrmann , Nigel Glover , Alexander Huss , Duncan Walker

We use an Effective Charges (ECH) method to extract Lambda-MS-bar, and hence alpha_s(M_z), from event shape moments in e+e- annihilation. We compare these results with ones obtained using standard MS-bar perturbation theory. The ECH method…

High Energy Physics - Phenomenology · Physics 2015-05-30 C. J. Maxwell , K. E. Morgan

The recent determination of the $\beta$--function of the QCD running coupling $\alpha_{\overline{MS}}(Q^2)$ to 5-loops{\color{blue},} provides a verification of the convergence of a novel method for determining the fundamental QCD parameter…

High Energy Physics - Phenomenology · Physics 2017-09-11 A. Deur , S. J. Brodsky , G. F. de Teramond