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Related papers: Two-loop splitting in double parton distributions

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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

In this paper, we present a detailed study of the unpolarized nucleon parton distribution function (PDF) employing the approach of parton pseudo-distribution functions. We perform a systematic analysis using three lattice ensembles at two…

High Energy Physics - Lattice · Physics 2020-01-29 Bálint Joó , Joseph Karpie , Kostas Orginos , Anatoly Radyushkin , David Richards , Savvas Zafeiropoulos

Double parton distribution functions (DPDFs) are used in the QCD description of double parton scattering. The DPDFs evolve with hard scales through QCD evolution equations which obey nontrivial momentum and valence quark number sum rules.…

High Energy Physics - Phenomenology · Physics 2014-07-30 Krzysztof Golec-Biernat , Emilia Lewandowska

A key ingredient in the description of double parton distributions is their scale dependence. If the colour of each individual parton is summed over, the distributions evolve with the same DGLAP kernels as ordinary parton distributions.…

High Energy Physics - Phenomenology · Physics 2023-05-24 Markus Diehl , Florian Fabry , Alexey Vladimirov

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 perform a two-loop calculation in Light Cone Perturbation Theory (LCPT) to evaluate the next-to-leading order nonsinglet splitting function. Our calculation demonstrates the methodology and feasibility of performing higher order…

High Energy Physics - Phenomenology · Physics 2026-01-16 Tuomas Lappi , Risto Paatelainen , Mikko Seppälä

We present the next-to-next-to-next-to-leading order (N^3LO) contributions to the non-singlet splitting functions for both parton distribution and fragmentation functions in perturbative QCD. The exact expressions are derived for the terms…

High Energy Physics - Phenomenology · Physics 2017-10-25 S. Moch , B. Ruijl , T. Ueda , J. A. M. Vermaseren , A. Vogt

We show that double parton distributions, which are important in describing double parton scattering processes in hadron collisions, can be directly computed from correlations of equal-time nonlocal Euclidean operators on the lattice in the…

High Energy Physics - Phenomenology · Physics 2023-05-12 Jian-Hui Zhang

We present a next-to-next-to-leading order (NNLO) global QCD analysis of the proton's helicity parton distribution functions (PDFs), the first of its kind. To obtain the distributions, we use data for longitudinal spin asymmetries in…

High Energy Physics - Phenomenology · Physics 2025-03-31 Ignacio Borsa , Daniel de Florian , Rodolfo Sassot , Marco Stratmann , Werner Vogelsang

We briefly discuss the status of double parton scattering (DPS) on both theoretical and experimental sides and summarize the state of the naive DPS model, where the scatterers are taken completely independent. We then elaborate on some of…

High Energy Physics - Phenomenology · Physics 2015-08-12 Tomas Kasemets

We consider double parton distribution functions (dPDFs), essential quantities in double parton scattering (DPS) studies, which encode novel non perturbative insight on the partonic proton structure. We develop the formalism to extract this…

High Energy Physics - Phenomenology · Physics 2019-10-02 Matteo Rinaldi , Federico Alberto Ceccopieri

Double parton distribution functions (dPDFs), measurable in hadron-hadron collisions and encoding information on how partons inside a proton are correlated among each other, could represent a new tool to explore the three dimensional…

High Energy Physics - Phenomenology · Physics 2017-04-03 Matteo Rinaldi , Sergio Scopetta , Vicente Vento , Marco Traini , Federico Alberto Ceccopieri

Using the approach based on conformal symmetry we calculate the two-loop coefficient function for the vector flavor-nonsinglet contribution to deeply-virtual Compton scattering (DVCS). The analytic expression for the coefficient function in…

High Energy Physics - Phenomenology · Physics 2021-08-03 V. M. Braun , A. N. Manashov , S. Moch , J. Schoenleber

Using the explicit form of the known single distribution functions (the Green's functions) in the double logarithm approximation of perturbative QCD, we analyze the structure of splitting diagrams as a source of double parton perturbative…

High Energy Physics - Phenomenology · Physics 2013-05-30 M. G. Ryskin , A. M. Snigirev

We provide a first study of Mellin moments of double parton distributions (DPDs) in the nucleon on the lattice, where we consider several combinations of quark flavors and polarizations. These are accessible through two-current…

High Energy Physics - Lattice · Physics 2021-09-30 Christian Zimmermann

We outline the recent results on the two-loop electroweak contributions to the electron-electron scattering cross sections and asymmetries. Although the two-loop corrections are strongly suppressed relative to the one-loop corrections, they…

High Energy Physics - Phenomenology · Physics 2014-11-18 A. Aleksejevs , S. Barkanova , V. Zykunov

We perform the analysis of the existing inclusive deep inelastic scattering (DIS) data within NNLO QCD approximation. The parton distributions functions (PDFs) and the value of strong coupling constant $\alpha_{s}(M_Z)=0.1143\pm0.0013…

High Energy Physics - Phenomenology · Physics 2015-06-25 Alekhin Sergey

We investigate the double parton distributions (DPDs) for a positronium-like bound state using light-front QED. We incorporate the higher Fock three particle component of the state, that includes a photon. We obtain the overlap…

High Energy Physics - Phenomenology · Physics 2019-11-06 Chandan Mondal , Asmita Mukherjee , Sreeraj Nair

Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and…

High Energy Physics - Phenomenology · Physics 2017-08-02 Markus Diehl , Jonathan R. Gaunt , Kay Schönwald

We present a fully analytic computation of the complete electron and photon structure functions, or QED lepton parton distribution functions (PDFs) up to two-loop order. Our computation is performed using modern techniques of reduction to…

High Energy Physics - Phenomenology · Physics 2025-09-23 Marvin Schnubel , Robert Szafron