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The notion of the Jacob's ladders, reversely iterated integrals and the $\zeta$-factorization is used in this paper in order to obtain new results in study of the function $\arg\zf$. Namely, we obtain new formulae for non-local and…

Classical Analysis and ODEs · Mathematics 2015-06-29 Jan Moser

Factorization scheme analysis of $F_2^{\gamma}(x,Q^2)$ in the next-to-leading order QCD is revisited. It is emphasized that the presence of the inhomogeneous term in the evolution equations for quark distribution functions of the photon…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jiri Chyla

Transverse momentum dependent parton distribution functions are a key ingredient in the description of spin and azimuthal asymmetries in deep-inelastic scattering processes. Recent results from non-perturbative calculations in effective…

High Energy Physics - Phenomenology · Physics 2010-02-04 H. Avakian , A. V. Efremov , P. Schweitzer , O. V. Teryaev , F. Yuan , P. Zavada

We calculate the non-forward quark matrix elements for operators with two covariant derivatives in one-loop lattice perturbation theory using Wilson fermions. These matrix elements are needed in the renormalisation of the second moment of…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , H. Perlt , P. E. L. Rakow , A. Schäfer , G. Schierholz , A. Schiller

The conventional NLO parton model is enough for the description of total cross sections and one-particle distributions. In the case of two-particle correlations, the collinear approximation has failed, and it is necessary to account for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. M. Shabelski

The second Mellin moments $\langle x\rangle$ of the nucleon's unpolarized, polarized, and transversity parton distribution functions (PDFs) are computed. Two lattice QCD ensembles at the physical pion mass are used: these were generated…

We construct a set of parton distribution functions (PDFs) in which fixed-order NLO and NNLO calculations are supplemented with soft-gluon (threshold) resummation up to NLL and NNLL accuracy respectively, suitable for use in conjunction…

High Energy Physics - Phenomenology · Physics 2015-10-13 Marco Bonvini , Simone Marzani , Juan Rojo , Luca Rottoli , Maria Ubiali , Richard D. Ball , Valerio Bertone , Stefano Carrazza , Nathan P. Hartland

Applications of perturbative QCD to deeply virtual Compton scattering process require a generalization of usual parton distributions for the case when long-distance information is accumulated in nonforward matrix elements of quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-30 Anatoly V. Radyushkin

In this talk we reexamine the possibility of evaluating parton distribution functions from lattice simulations. We show that, while in principle individual moments can be extracted from lattice data, in all cases the process of…

High Energy Physics - Lattice · Physics 2018-11-27 Giancarlo Rossi , Massimo Testa

Parton distribution functions (DFs) have long been recognised as key measures of hadron structure. Today, theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction…

High Energy Physics - Phenomenology · Physics 2024-11-12 Yang Yu , Craig D. Roberts

We consider the renormalisation of lattice QCD operators with one and two covariant derivatives related to the first and second moments of generalised parton distributions and meson distribution amplitudes. Employing the clover fermion…

High Energy Physics - Lattice · Physics 2010-10-28 M. Göckeler , R. Horsley , H. Perlt , P. E. L. Rakow , A. Schäfer , G. Schierholz , A. Schiller

We consider the analytic continuation of the transfer function associated with a 2x2 operator matrix having unbounded couplings into unphysical sheets of its Riemann surface. We construct a family of non-selfadjoint operators which…

Spectral Theory · Mathematics 2007-05-23 V. Hardt , R. Mennicken , A. K. Motovilov

Applications of perturbative QCD to hard exclusive electroproduction processes in the Bjorken limit at small invariant momentum transfer t bring in a new type of parton distributions which have hybrid properties, resembling both the parton…

High Energy Physics - Phenomenology · Physics 2009-10-30 Anatoly V. Radyushkin

We describe the architecture and functionalities of a C++ software framework, coined PARTONS, dedicated to the phenomenology of Generalized Parton Distributions. These distributions describe the three-dimensional structure of hadrons in…

High Energy Physics - Phenomenology · Physics 2018-04-04 B. Berthou , D. Binosi , N. Chouika , L. Colaneri , M. Guidal , C. Mezrag , H. Moutarde , J. Rodríguez-Quintero , F. Sabatié , P. Sznajder , J. Wagner

Data on the nucleon spin structure suggests that the $u$ (and $d$) quark distributions in the $\Lambda$ hyperon may be polarized. If this correlation carries over into fragmentation, then the study of polarized $\Lambda$'s in the current…

High Energy Physics - Phenomenology · Physics 2010-01-06 R. L. Jaffe

This work focuses on applications of perturbative QCD (pQCD) and collinear factorization theorem to hard particle production in nuclear and hadronic collisions at the BNL-RHIC and CERN-LHC colliders. The emphasis is on nuclear parton…

High Energy Physics - Phenomenology · Physics 2014-08-29 Ilkka Helenius

We give an overview of the theory for generalized parton distributions. Topics covered are their general properties and physical interpretation, the possibility to explore the three-dimensional structure of hadrons at parton level, their…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Diehl

Motivated by the need to correct the potentially large kinematic errors in approximations used in the standard formulation of perturbative QCD, we reformulate deeply inelastic lepton-proton scattering in terms of gauge invariant, universal…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. C. Collins , T. C. Rogers , A. M. Staśto

We review the calculation of moments of both the polarized and unpolarized parton distribution functions of the nucleon in lattice QCD, and in particular their extrapolation to the physical region. We also discuss the reconstruction of the…

High Energy Physics - Lattice · Physics 2008-11-26 W. Detmold , W. Melnitchouk , A. W. Thomas

The class of interference fragmentation functions, arising from interference among different hadron production channels, is reconsidered. Their symmetry properties with respect to chiral transformations allow building spin asymmetries where…

High Energy Physics - Phenomenology · Physics 2017-08-23 M. Radici