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Related papers: Virtual Photon Structure Functions to NNLO in QCD

200 papers

The theoretical framework for a next-to-leading order QCD analysis of the spin-dependent parton densities Delta f^{gamma}(x,Q^2) of the longitudinally polarized photon and of its structure function g_1^{gamma}(x,Q^2) is reviewed in some…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Stratmann

The flux of papers from electron positron colliders containing data on the photon structure function ended naturally around 2005. It is thus timely to review the theoretical basis and confront the predictions with a summary of the…

High Energy Physics - Phenomenology · Physics 2015-08-05 Ch. Berger

We present a systematic analysis of the processes $e^+ ~e^- \rightarrow e^+ ~e^- X$ to study the polarised and unpolarised photon structure functions. The effect of target photon mass, which manifests itself as new singly polarised…

High Energy Physics - Phenomenology · Physics 2015-06-25 Prakash Mathews , V. Ravindran

A measurement of the derivative (d ln F_2 / d lnx)_(Q^2)= -lambda(x,Q^2) of the proton structure function F_2 is presented in the low x domain of deeply inelastic positron-proton scattering. For 5*10^(-5)<=x<=0.01 and Q^2>=1.5 GeV^2,…

High Energy Physics - Experiment · Physics 2010-03-25 H1 Collaboration , C. Adloff

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

We review the nucleon's polarized structure functions from the viewpoint of gauge invariant, nonlocal light-cone operators in QCD. We discuss a systematic treatment of the polarized structure functions and the corresponding parton…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. Kodaira

We compute the structure function, transverse momentum dependent parton distributions (TMDs), and generalized parton distributions (GPDs) for the physical photon from the light-front quantum electrodynamics (QED) Hamiltonian, determined for…

High Energy Physics - Phenomenology · Physics 2023-02-28 Sreeraj Nair , Chandan Mondal , Xingbo Zhao , Asmita Mukherjee , James P. Vary

We determine, in the antenna subtraction framework for handling infrared divergences in higher order QCD calculations, the real-virtual antenna functions for processes involving the production of a pair of massive quarks by an uncolored…

High Energy Physics - Phenomenology · Physics 2015-06-22 Oliver Dekkers , Werner Bernreuther

In deep inelastic electron-photon scattering in leading order QED, egamma->egamma*gamma->effbar, there are four non-zero structure functions. We calculate them for real photons retaining the full dependence on the fermion mass, and show…

High Energy Physics - Phenomenology · Physics 2009-10-31 Richard Nisius , Michael H. Seymour

The status of measurements and interpretation of the proton structure function F2 is summarized. The measurements are subjected to DGLAP fits, from which the gluon density is extracted and a comparison to measurements of F2c is performed.…

High Energy Physics - Experiment · Physics 2016-11-23 Christoph Amelung

The factorization of the amplitude for the deeply virtual Compton scattering (DVCS) process gamma*(Q) gamma -> gamma gamma at high Q2 is demonstrated in two distinct kinematical domains, allowing to define the photon generalized parton…

High Energy Physics - Phenomenology · Physics 2009-01-14 M. El Beiyad , S. Friot , B. Pire , L. Szymanowski , S. Wallon

New measurements are presented of the photon structure function F_2^gamma(Q) at four values of Q^2 between 9 and 59 GeV/c^2 based on data collected with the OPAL detector at centre-of-mass energies of 161-172 GeV, with a total integrated…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

The electromagnetic and weak structure functions of the photon can be studied in the deep inelastic electron-photon processes e+gamma -> e+X and e+gamma -> nu+X. While at low energies only virtual photon exchange is operative in the…

High Energy Physics - Phenomenology · Physics 2011-02-01 A. Gehrmann-De Ridder , H. Spiesberger , P. M. Zerwas

In this paper we present the result of a direct QCD sum rule calculation of the transition form factor \gamma\gamma* -> pi^o in the region of moderately large invariant momentum Q^2 > 1GeV^2 of the virtual photon. In contrast to pQCD, we…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Radyushkin , R. Ruskov

We perform joint fits using measurements of the proton structure functions $F_2(x,Q^2)$ and $F_L(x,Q^2)$, of the photon structure function $F_2^\gamma(x,Q^2)$ and of the total cross-sections $\sigma\left( \gamma p \rightarrow X\right)$ and…

High Energy Physics - Phenomenology · Physics 2020-12-08 Artur Amorim , Miguel S. Costa

We present a simultaneous extraction of the moments of $F_2$ and $F_L$ structure functions of the proton for a range of photon virtuality, $Q^2$. This is achieved by computing the forward Compton amplitude on the lattice utilizing the…

We present the results of our QCD analysis for nonsinglet unpolarized quark distributions and structure function $F_2(x,Q^2)$. New parameterizations are derived for the nonsinglet quark distributions for the kinematic wide range of $x$ and…

High Energy Physics - Phenomenology · Physics 2008-12-25 Ali N. Khorramian , S. Atashbar Tehrani

We report on a high statistics quenched lattice QCD calculation of the deep-inelastic structure functions $F_1$, $F_2$, $g_1$ and $g_2$ of the proton and neutron. The theoretical basis for the calculation is the operator product expansion.…

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

Recent results from NLO QCD calculations for inclusive jet cross sections in gamma^*-gamma scattering at e+e- colliders, especially for LEP, are reported. The virtuality Q^2 of the virtual photon is non-zero and can be unlimited large. The…

High Energy Physics - Phenomenology · Physics 2011-08-11 B. Pötter

We investigated top quark effects on virtual photon structure functions by pQCD. We include the top quark mass effects on the virtual photon structure function with the quark parton model and with the operator product expansion up to the…

High Energy Physics - Phenomenology · Physics 2011-08-17 Yoshio Kitadono