English
Related papers

Related papers: The massive 3-loop operator matrix elements with t…

200 papers

We have calculated the fermionic contributions to the flavour non-singlet structure functions in deep-inelastic scattering (DIS) at third order of massless perturbative QCD. We discuss their implications for the threshold resummation at the…

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

We compute the two-loop term in the perturbation series for the quark-mass in the lattice Heavy Quark Effective Theory. This is an ingredient in the matching factor required to obtain the $b$-quark mass from lattice simulations of the HQET.…

High Energy Physics - Lattice · Physics 2009-10-09 G. Martinelli , C. T. Sachrajda

We describe the calculation of the two--loop massive operator matrix elements for massive external fermions. These matrix elements are needed for the calculation of the $O(\alpha^2)$ initial state radiative corrections to $e^+e^-$…

High Energy Physics - Phenomenology · Physics 2009-04-14 J. Blümlein , A. De Freitas , W. van Neerven

In this letter we continue the calculation of master integrals for massless three-loop form factors by giving analytical results for those integrals which are relevant for the fermionic contributions proportional to N_F^2, N_F*N, and N_F/N.…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Heinrich , T. Huber , D. Maitre

We calculate the massless unpolarized Wilson coefficients for deeply inelastic scattering for the structure functions $F_2(x,Q^2), F_L(x,Q^2), x F_3(x,Q^2)$ in the $\overline{\sf MS}$ scheme and the polarized Wilson coefficients of the…

High Energy Physics - Phenomenology · Physics 2022-12-14 J. Blümlein , P. Marquard , C. Schneider , K. Schönwald

We compute the relation between the pole mass and the kinetic mass of a heavy quark to three loops. Using the known relation between the pole and the $\overline{\rm MS}$ mass we obtain precise conversion relations between the $\overline{\rm…

High Energy Physics - Phenomenology · Physics 2022-02-08 Matteo Fael , Kay Schönwald , Matthias Steinhauser

We consider Quantum Chromodynamics with external vector, axial-vector, scalar and pseudo-scalar currents and compute three-loop corrections to the corresponding vertex function taking into account massive quarks. We consider all non-singlet…

High Energy Physics - Phenomenology · Physics 2022-09-14 Matteo Fael , Fabian Lange , Kay Schönwald , Matthias Steinhauser

We present an analytic calculation of electron and tau O(alpha^3) loop effects on the muon anomalous magnetic moment. Computation of such three-loop diagrams with three mass scales is possible using asymptotic and eikonal expansions. An…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , Maciej Skrzypek

We present the two-loop corrected operator matrix elements calculated in N-dimensional regularization up to the finite terms which survive in the limit $\epsilon = N - 4 \to 0 $. The anomalous dimensions of the local operators have been…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Matiounine , J. Smith , W. L. van Neerven

We describe a method to numerically compute multi-loop integrals, depending on one dimensionless parameter $x$ and the dimension $d$, in the whole kinematic range of $x$. The method is based on differential equations, which, however, do not…

High Energy Physics - Phenomenology · Physics 2021-10-13 Matteo Fael , Fabian Lange , Kay Schönwald , Matthias Steinhauser

The quarkonic contributions to the three-loop heavy-quark form factors for vector, axial-vector, scalar and pseudoscalar currents are described by closed form difference equations for the expansion coefficients in the limit of small…

High Energy Physics - Phenomenology · Physics 2023-07-07 Johannes Blümlein , Abilio De Freitas , Peter Marquard , Narayan Rana , Carsten Schneider

In this paper we compute the relation between heavy quark masses defined in the modified minimal subtraction and on-shell scheme. Detailed results are presented for all coefficients of the SU$(N_c)$ colour factors. The reduction of the…

High Energy Physics - Phenomenology · Physics 2016-11-23 Peter Marquard , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser , David Wellmann

Increasing demand for computational power has initiated the hunt for energy efficient and stable memory devices. This is the overarching motivation behind the recent rise of \textit{orbitronics}, which looks to harness the orbital angular…

Mesoscale and Nanoscale Physics · Physics 2026-03-06 James H. Cullen , Dimitrie Culcer

The calculation of massive three-loop QCD form factors using in particular the large moments method has been successfully applied to quarkonic contributions in [1]. We give a brief review of the different steps of the calculation and report…

High Energy Physics - Phenomenology · Physics 2024-08-14 J Blümlein , A. De Freitas , P. Marquard , C. Schneider

Exclusive rare decays mediated by $b\to s\ell\ell$ transitions receive contributions from four-quark operators that cannot be naively expressed in terms of local form factors. Instead, one needs to calculate a matrix element of a bilocal…

High Energy Physics - Phenomenology · Physics 2020-04-07 Hrachia M. Asatrian , Christoph Greub , Javier Virto

A physically defined QCD coupling parameter naturally incorporates massive quark flavor thresholds in a gauge invariant, renormalization scale independent and analytical way. In this paper we summarize recent results for the finite-mass…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michael Melles

We calculate all contributions $\propto T_F$ to the polarized three-loop anomalous dimensions in the M-scheme using massive operator matrix elements and compare to results in the literature. This includes the complete anomalous dimensions…

High Energy Physics - Phenomenology · Physics 2019-09-25 A. Behring , J. Blümlein , A. De Freitas , A. Goedicke , S. Klein , A. von Manteuffel , C. Schneider , K. Schönwald

The order $\alpha_s$ corrections to the Wilson coefficients of the dipole operators ($O_7,O_8$) at the matching scale $\mu =m_W$ are a crucial ingredient for a complete next- to-leading logarithmic calculation of the branching ratio for $b…

High Energy Physics - Phenomenology · Physics 2014-11-17 Christoph Greub , Tobias Hurth

We perform an extensive study of the scale dependence of flavor-singlet contributions to the structure function g_2(x,Q^2) in polarized deep-inelastic scattering. We find that the mixing between quark-antiquark-gluon and three-gluon twist-3…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. M. Braun , G. P. Korchemsky , A. N. Manashov

We study matrix elements of the "chromomagnetic" operator on the lattice. This operator is contained in the strangeness-changing effective Hamiltonian which describes electroweak effects in the Standard Model and beyond. Having dimension 5,…

High Energy Physics - Lattice · Physics 2014-10-06 M. Constantinou , M. Costa , R. Frezzotti , V. Lubicz , G. Martinelli , D. Meloni , H. Panagopoulos , S. Simula
‹ Prev 1 4 5 6 7 8 10 Next ›