English
Related papers

Related papers: Unpolarized QED parton distribution functions in N…

200 papers

We present numerical solutions of the $Q^2$ evolution equations at next-to-leading order (NLO) for unpolarized and polarized parton distributions, in both the flavor non-singlet and singlet channels. The numerical method is based on a…

High Energy Physics - Phenomenology · Physics 2009-10-28 T. Weigl , W. Melnitchouk

We have computed the complete next-to-next-to-leading order (NNLO) contributions to the splitting functions governing the evolution of unpolarized parton densities in perturbative QCD. Our results agree with all partial results available in…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Moch , J. A. M. Vermaseren , A. Vogt

Iterative solution of QED evolution equations for non-singlet electron structure functions is considered. Analytical expressions in the fourth and fifth orders are presented in terms of splitting functions. Relation to the existing…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. B. Arbuzov

We summarize recent results on the evolution of unpolarized parton densities and deep-inelastic structure functions in massless perturbative QCD. Due to last year's extension of the integer-moment calculations of the three-loop splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt

We determine the two-loop 'time-like' Altarelli-Parisi splitting functions, appearing in the next-to-leading order Q^2-evolution equations for fragmentation functions, via analytic continuation of the corresponding 'space-like' splitting…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Stratmann , W. Vogelsang

Numerical solution of DGLAP $Q^2$ evolution equations is studied for polarized parton distributions by using a ``brute-force" method. NLO contributions to splitting functions are recently calculated,and they are included in our analysis.…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Hirai , S. Kumano , M. Miyama

We have calculated the splitting functions governing the evolution of the unpolarized parton distributions of the photon at the next-to-next-to-leading order (NNLO) of massless perturbative QCD. The results, presented here mainly in terms…

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

In this paper we present a new and efficient analytical solutions for evolving the QED$\otimes$QCD DGLAP evolution equations in mellin space and obtain the parton distribution functions (PDFs) in perturbative QCD including the QED…

High Energy Physics - Phenomenology · Physics 2017-10-04 Marzieh Mottaghizadeh , Fatemeh Taghavi Shahri , Parvin Eslami

The electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron have recently been computed at the next-to-leading logarithmic accuracy in QED, by adopting the $\overline{\rm MS}$ factorisation scheme. We…

High Energy Physics - Phenomenology · Physics 2021-12-22 Stefano Frixione

We compute the next-to-next-to-leading order (NNLO) contributions to the splitting functions governing the evolution of the unpolarized flavour-singlet parton densities in perturbative QCD. The exact expressions are presented in both…

High Energy Physics - Phenomenology · Physics 2010-04-05 A. Vogt , S. Moch , J. A. M. Vermaseren

Higher-order QED radiative corrections to muon decay spectrum are evaluated within the QED structure function approach in the next-to-leading order logarithmic approximation. New analytical results are given in the…

High Energy Physics - Phenomenology · Physics 2023-12-19 A. B. Arbuzov , U. E. Voznaya

We present an analytical solution for the evolution of parton distributions incorporating mixed-order QCD $\otimes$ QED corrections, addressing both polarized and unpolarized cases. Using the Altarelli-Parisi kernels extended to mixed…

High Energy Physics - Phenomenology · Physics 2026-02-16 Daniel de Florian , Lucas Palma Conte

We discuss the effect of QED corrections in the evolution of polarized parton distributions. We solve the corresponding evolution equations exactly to ${\cal O}(\alpha )$ and ${\cal O}(\alpha_s^2)$ in Mellin $N$-space, extending the…

High Energy Physics - Phenomenology · Physics 2024-10-30 Daniel de Florian , Lucas Palma Conte

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

We compute the next-to-next-to-leading order (NNLO) contributions to the three splitting functions governing the evolution of unpolarized non-singlet combinations of quark densities in perturbative QCD. Our results agree with all partial…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Moch , J. A. M. Vermaseren , A. Vogt

A next-to-leading order QCD analysis of spin asymmetries and structure functions in polarized deep inelastic lepton nucleon scattering is presented within the framework of the radiative parton model. A consistent NLO formulation of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Gluck , E. Reya , M. Stratmann , W. Vogelsang

The Fortran package QCD-PEGASUS is presented. This program provides fast, flexible and accurate solutions of the evolution equations for unpolarized and polarized parton distributions of hadrons in perturbative QCD. The evolution is…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Vogt

By working in QED, we obtain the electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron at the next-to-leading logarithmic accuracy. The PDFs account for all of the universal effects of initial-state…

High Energy Physics - Phenomenology · Physics 2022-07-26 V. Bertone , M. Cacciari , S. Frixione , G. Stagnitto

The QCDNUM program numerically solves the evolution equations for parton densities and fragmentation functions in perturbative QCD. Un-polarised parton densities can be evolved up to next-to-next-to-leading order in powers of the strong…

High Energy Physics - Phenomenology · Physics 2010-11-23 M. Botje

We briefly discuss recent results on the evolution of unpolarized parton densities and structure functions in massless perturbative QCD. Present partial results on the next-to-next-to-leading order (NNLO) evolution kernels prove sufficient…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. L. van Neerven , A. Vogt
‹ Prev 1 2 3 10 Next ›