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Related papers: Four-loop QCD mixing of current-current operators

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We present the first results for the next-to-next-to leading order (NNLO) corrections to the semi-inclusive deep-inelastic scattering process in perturbative quantum chromodynamics. We consider the quark initiated flavor non-singlet process…

High Energy Physics - Phenomenology · Physics 2024-03-21 Saurav Goyal , Sven-Olaf Moch , Vaibhav Pathak , Narayan Rana , V. Ravindran

We match continuum and lattice heavy-light four-fermion operators at one loop in perturbation theory. For the heavy quarks we use nonrelativistic QCD and for the massless light quarks the highly improved staggered quark action. We include…

High Energy Physics - Lattice · Physics 2014-10-02 Christopher Monahan , Elvira Gamiz , Ron Horgan , Junko Shigemitsu

In this paper, we explicitly calculate the lower CPT-even one-loop quantum corrections in nonminimal Lorentz-violating spinor QED with all possible CPT-even dimension-5 operators. Within our calculations, we restrict ourselves to the cases…

High Energy Physics - Theory · Physics 2024-01-19 T. Mariz , M. Melo , J. R. Nascimento , A. Yu. Petrov

This paper summarizes the recent calculations of the masses and decay constants of the pseudoscalar mesons at the two-loop level, or NNLO, in Partially Quenched Chiral Perturbation Theory (PQxPT). Possible applications include chiral…

High Energy Physics - Lattice · Physics 2009-11-11 Timo A. Lahde , Johan Bijnens , Niclas Danielsson

QCD evolution equations in minimal subtraction schemes have a hidden symmetry: One can construct three operators that commute with the evolution kernel and form an $SL(2)$ algebra, i.e. they satisfy (exactly) the $SL(2)$ commutation…

High Energy Physics - Phenomenology · Physics 2016-04-20 V. M. Braun , A. N. Manashov , S. Moch , M. Strohmaier

We have computed the next-to-next-to-leading-order (NNLO) contributions to the evolution of unpolarized parton distributions in perturbative QCD. In this talk, we briefly recall why this huge computation was necessary and outline how it was…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Vogt , S. Moch , J. Vermaseren

Applying the light-cone sum rules (LCSR) approach, the next-to-leading-order (NLO) corrections to $B \to A$ form factors are calculated with the twist-two and twist-three $B$ meson light-cone distribution amplitudes (LCDAs) at leading power…

High Energy Physics - Phenomenology · Physics 2025-12-04 Fang-Zhou Di , Yu-Hao Liu

In this review some recent multi-loop results obtained in the framework of perturbative Quantum Chromodynamics (QCD) and Quantum Electrodynamics (QED) are discussed. After reviewing the most advanced techniques used for the computation of…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Steinhauser

We perform a systematic study of flavor-diagonal parity- and time-reversal-violating operators of dimension six which could arise from physics beyond the SM. We begin at the unknown high-energy scale where these operators originate. At this…

High Energy Physics - Phenomenology · Physics 2013-06-04 W. Dekens , J. de Vries

We compute four-point correlation functions of scalar composite operators in the N=4 supercurrent multiplet at order g^4 using the N=1 superfield formalism. We confirm the interpretation of short-distance logarithmic behaviours in terms of…

High Energy Physics - Theory · Physics 2009-10-31 M. Bianchi , S. Kovacs , G. C. Rossi , Ya. S. Stanev

We present a new analysis of the ratio epsilon'/epsilon which measures the direct CP violation in K\to\pi\pi decays. We use the 1/N_c expansion within the framework of the effective chiral lagrangian for pseudoscalar mesons. From general…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Hambye , P. H. Soldan

We consider the anomalous dimension of the flavor non-singlet twist-two quark operator of arbitrary Lorentz spin N at four loops in QCD and construct its contribution proportional to zeta(3) in analytic form by applying advanced methods of…

High Energy Physics - Phenomenology · Physics 2025-03-27 B. A. Kniehl , V. N. Velizhanin

We use the known values of the two loop Wilson coefficients and the three loop anomalous dimension matrix $\gamma(n)$ to perform a next-to-next-to leading order (NNLO) calculation of $ep$ deep inelastic scattering. Because $\gamma(n)$ is…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Santiago , F. J. Yndurain

The leading order coefficients of the beta-function of QCD are computed in a large N_f expansion. They are in agreement with the three loop MSbar calculation. The method involves computing the anomalous dimension of the operator (G^2_{mu…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. A. Gracey

We compute the next-to-next-to-leading order (NNLO) QCD corrections to the hadronic decay rates of the pseudoscalar quarkonia, at the lowest order in velocity expansion. The validity of NRQCD factorization for inclusive quarkonium decay…

High Energy Physics - Phenomenology · Physics 2017-12-27 Feng Feng , Yu Jia , Wen-Long Sang

We present the analytic total cross section of top quark pair production in electron-positron annihilation at next-to-next-to-leading order (NNLO) in Quantum Chromodynamics (QCD). By utilizing the optical theorem, the NNLO corrections are…

High Energy Physics - Phenomenology · Physics 2024-09-10 Long-Bin Chen , Jian Wang , Yefan Wang

We calculate the unpolarized and polarized three--loop anomalous dimensions and splitting functions $P_{\rm NS}^+, P_{\rm NS}^-$ and $P_{\rm NS}^{\rm s}$ in QCD in the $\overline{\sf MS}$ scheme by using the traditional method of…

High Energy Physics - Phenomenology · Physics 2021-09-15 J. Blümlein , P. Marquard , C. Schneider , K. Schönwald

D0 and CDF collaborations at the Fermilab Tevatron have searched for non-standard-model single top-quark production and set upper limits on the anomalous top quark flavor-changing neutral current (FCNC) couplings $\kappa^g_{tc}/\Lambda$ and…

High Energy Physics - Phenomenology · Physics 2009-02-27 Jia Jun Zhang , Chong Sheng Li , Jun Gao , Hao Zhang , Zhao Li , C. -P. Yuan , Tzu-Chiang Yuan

We present the first computation of next-to-next-to-leading order (NNLO) pure QED and mixed QCD$\otimes$QED corrections to unpolarized and polarized semi-inclusive deep-inelastic scattering (SIDIS). Building on our previous NNLO QCD…

High Energy Physics - Phenomenology · Physics 2025-10-22 Saurav Goyal , Roman N. Lee , Sven-Olaf Moch , Vaibhav Pathak , V. Ravindran

In this talk we present the result for the $n_f$ dependent piece of the three-loop cusp anomalous dimension in QCD. Remarkably, it is parametrized by the same simple functions appearing in analogous anomalous dimensions in ${\mathcal N}=4$…

High Energy Physics - Theory · Physics 2014-08-21 Andrey Grozin , Johannes M. Henn , Gregory P. Korchemsky , Peter Marquard