English
Related papers

Related papers: On QCD analysis of stucture function $F_2^{\gamma}…

200 papers

The QCD treatment of the photon structure beyond the leading order is discussed with emphasis on a proper choice of the factorization scheme and/or the boundary conditions. Recent parametrizations of the photon's parton content are examined…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Vogt

The computation of the NLO-QCD corrections to the cross sections for W \gamma \gamma production in hadronic collisions is presented. We consider the case of real photons in the final state, but include full leptonic decays of the W.…

High Energy Physics - Phenomenology · Physics 2011-07-05 G. Bozzi , F. Campanario , M. Rauch , D. Zeppenfeld

We investigate the effect of the structure function F_L in global parton analyses of deep inelastic and related hard scattering data. We perform NLO and NNLO analyses which include the reduced cross section HERA data at high y, as well as…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , W. J. Stirling , R. S. Thorne

A new analysis of the radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our paper [1], is presented. We perform four new global fits to the experimental data for…

High Energy Physics - Phenomenology · Physics 2011-01-25 F. Cornet , P. Jankowski , M. Krawczyk

QCD corrections to the QED formula for parton distribution functions of the longitudinal virtual photon are derived in the leading--logarithmic approximation. It is shown that the resulting PDF satisfy the same homogeneous evolution…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jiri Chyla

Interactions of virtual photons are analyzed in terms of photon structure. It is argued that the concept of parton distribution functions is phenomenologically very useful even for highly virtual photons involved in hard collisions. This…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jiri Chyla , Marek Tasevsky

Gluon distributions in real and virtual photons are calculated using evolution equations in the NLO approximation. The quark distributions in the photon determined on the basis of the QCD sum rule approach in ref.[1] are taken as an input.…

High Energy Physics - Phenomenology · Physics 2019-08-17 B. L. Ioffe , A. Oganesian

The photon parton distribution function (PDF) of the proton is crucial for precise comparisons of LHC cross sections with theoretical predictions. However, it was previously affected by very large uncertainties of around ${\cal O}(100\%)$…

High Energy Physics - Phenomenology · Physics 2024-08-26 Aneesh Manohar , Paolo Nason , Gavin Salam , Giulia Zanderighi

Measurements of the QED structure of the photon based on the reaction ee --> ee \gamma(*)(P^2)\gamma*(Q^2) --> ee mumu are discussed. This review is an update of the discussion of the results on the QED structure of the photon presented in…

High Energy Physics - Experiment · Physics 2019-08-14 Richard Nisius

The QCD structure of the electron is defined and calculated. The leading order splitting functions are extracted, showing an important contribution from $\gamma$-$Z$ interference. Leading logarithmic QCD evolution equations are constructed…

High Energy Physics - Phenomenology · Physics 2009-10-28 Wojciech Slominski , Jerzy Szwed

Nuclear parton distribution functions (NPDFs) are determined by a global analysis of experimental measurements on structure-function ratios F_2^A/F_2^{A'} and Drell-Yan cross section ratios \sigma_{DY}^A/\sigma_{DY}^{A'}, and their…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Hirai , S. Kumano , T. -H. Nagai

The QCD corrections to photon structure functions are defined in a way consistent with the factorization scheme invariance. It is shown that the conventional DIS$_{\gamma}$ factorization scheme does not respect this invariance and is thus…

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

In this paper the two-photon interactions at high energies are investigated considering different approaches for the QCD dynamics. In particular, we calculate the $\gamma^* \gamma^*$ total cross section in different theoretical approches…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. P. Goncalves , M. V. T. Machado , W. K. Sauter

The unique nature of the photon can be investigated in hitherto unexplored kinematic regions at LEP2. We discuss the theoretical significance of deep inelastic measurements and present a prescription that allows a theoretically and…

High Energy Physics - Phenomenology · Physics 2008-02-03 J. R. Forshaw , M. H. Seymour

Q$^2$ variation of the nuclear-structure-function ratio $F_2^A(x,Q^2)/F_2^D(x,Q^2)$ is investigated in a parton model with Q$^2$-rescaling and parton-recombination effects. Calculated results are compared with the NMC (New Muon…

High Energy Physics - Phenomenology · Physics 2009-09-25 S. Kumano

The present knowledge of the structure of the photon based on measurements of photon structure functions is discussed. This review covers QED structure functions and the hadronic structure function F_2^gamma.

High Energy Physics - Experiment · Physics 2007-05-23 Richard Nisius

A pion distribution amplitude, derived from nonlocal QCD sum rules, has been employed to calculate $F_{\gamma^*\gamma\to\pi}(Q^2)$ using light-cone sum rules, and $F_{\pi}(Q^2)$ in NLO QCD perturbation theory. Predictions are presented for…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. G. Stefanis , A. P. Bakulev , S. V. Mikhailov , K. Passek-Kumerički , W. Schroers

We analyse the data for the proton structure function $F_2$ over the entire $Q^2$ domain, including especially low $Q^2$, in terms of perturbative and non-perturbative QCD contributions. The small distance configurations are given by…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. D. Martin , M. G. Ryskin , A. Stasto

The photon is explored as an object to test the applications of QCD to the perturbatively calculable collinear parton distributions. We investigate analytic properties of DVCS amplitudes and related sum rules of generalized parton…

High Energy Physics - Phenomenology · Physics 2012-09-25 I. R. Gabdrakhmanov , O. V. Teryaev

The parton distributions functions (PDFs) derived from the NNLO QCD analysis of existing light-targets deep-inelastic-scattering data are presented. The NLO and NNLO PDFs are compared in order to analyze perturbative stability of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Alekhin