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Related papers: Deeply Virtual Compton Scattering at HERA and pers…

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The HERA diffractive structure function data are interpreted in terms of `diffractive parton distributions' which satisfy DGLAP evolution. These distributions are modeled assuming that the scattering takes place off a colour singlet…

High Energy Physics - Phenomenology · Physics 2007-05-23 Z. Kunszt , W. J. Stirling

We show how quark-hadron duality can emerge for valence spin averaged structure functions, and for the non-forward distributions of Deeply Virtual Compton Scattering. Novel factorisations of the non-forward amplitudes are proposed. Some…

High Energy Physics - Phenomenology · Physics 2009-11-07 Frank E. Close , Qiang Zhao

A detailed analysis is presented of the diffractive deep-inelastic scattering process $ep\to eXY$, where $Y$ is a proton or a low mass proton excitation carrying a fraction $1 - \xpom > 0.95$ of the incident proton longitudinal momentum and…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

We present a Machine Learning based approach to the cross section and asymmetries for deeply virtual Compton scattering from an unpolarized proton target using both an unpolarized and polarized electron beam. Machine learning methods are…

High Energy Physics - Phenomenology · Physics 2021-07-07 Jake Grigsby , Brandon Kriesten , Joshua Hoskins , Simonetta Liuti , Peter Alonzi , Matthias Burkardt

We evaluate within a microscopic calculation the contributions of both coherent and incoherent deeply virtual Compton scattering from a spin-0 nucleus. The coherent contribution is obtained when the target nucleus recoils as a whole,…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Liuti , S. K. Taneja

Positron initiated deeply virtual Compton scattering (DVCS) off $^4$He and $^3$He nuclei is described. The way the so-called $d-$term could be obtained from the real part of the relevant Compton form factor is summarized, and the importance…

High Energy Physics - Phenomenology · Physics 2021-09-29 Sara Fucini , Mohammad Hattawy , Matteo Rinaldi , Sergio Scopetta

Interactions of virtual photons are analyzed in terms of their parton distribution functions. It is shown that the concept of parton distribution functions is phenomenologically very useful even for highly virtual photonds involved in hard…

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

The Weisberger relation, an exact statement of the parton model, elegantly relates a high-energy physics observable, the 1/x moment of parton distribution functions, to a nonperturbative low-energy observable: the dependence of the nucleon…

Nuclear Theory · Physics 2009-09-11 Stanley J. Brodsky , Felipe J. Llanes-Estrada , Adam P. Szczepaniak

Measurements of deeply virtual Compton scattering (DVCS) made at HERMES using 27.6 GeV $e^\pm$ beams and various internal polarized or unpolarized gaseous targets are discussed. Results are reported on the transverse target-spin asymmetry…

High Energy Physics - Experiment · Physics 2007-05-23 Zhenyu Ye

A unique feature of generalised parton distributions is their relation to the QCD energy-momentum tensor. In particular, they provide access to the mechanical properties of the proton i.e. the distributions of pressure and shear stress…

High Energy Physics - Phenomenology · Physics 2021-04-28 H. Dutrieux , C. Lorcé , H. Moutarde , P. Sznajder , A. Trawiński , J. Wagner

We consider Semi-Exclusive Deeply Virtual Compton Scattering, gamma* p \to gamma Y (SECS), where Y is an inclusive state of intermediate mass, \Lambda_QCD << m_Y << Q. When the photon is produced with a large transverse momentum k_T \sim…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paul Hoyer , Heidi Virtanen

The first observation of an azimuthal cross--section asymmetry with respect to the charge of the incoming lepton beam is reported from a study of hard exclusive electroproduction of real photons. The data have been accumulated by the HERMES…

High Energy Physics - Experiment · Physics 2012-08-03 The HERMES Collaboration , A. Airapetian

Using the available data on deeply virtual Compton scattering (DVCS) off protons and utilizing neural networks enhanced by the dispersion relation constraint, we determine six out of eight leading Compton form factors in the valence quark…

High Energy Physics - Phenomenology · Physics 2020-07-02 Marija Cuic , Kresimir Kumericki , Andreas Schafer

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

We report on the access of generalized parton distributions (GPDs) from deeply virtual Compton scattering (DVCS) measurements. We also point out that such measurements at a proposed high-luminosity electron-ion collider (EIC) provide…

High Energy Physics - Phenomenology · Physics 2012-06-01 Kresimir Kumericki , Dieter Mueller

We study recent Deeply Virtual Compton scattering (DVCS) data within a dual parameterization of the Generalized Parton Distributions (GPDs). This parameterization allows to quantify the maximum amount of information, that can be extracted…

High Energy Physics - Phenomenology · Physics 2008-03-18 Maxim V. Polyakov , Marc Vanderhaeghen

This talk explores the impact that the Hermes experiment has had regarding knowledge of the Deeply Virtual Compton Scattering process. We discuss the various measurements that Hermes has contributed to the library of DVCS knowledge, with…

High Energy Physics - Experiment · Physics 2015-06-12 Morgan Murray

The hard exclusive electroproduction processes provide new information about hadronic structure accumulated in nonforward parton distributions. The NFPD's are universal hybrid functions having the properties of parton densities, hadronic…

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

Neural networks are utilized to fit Compton form factor H to HERMES data on deeply virtual Compton scattering off unpolarized protons. We used this result to predict the beam charge-spin assymetry for muon scattering off proton at the…

High Energy Physics - Phenomenology · Physics 2011-10-20 Kresimir Kumericki , Dieter Mueller , Andreas Schafer