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Related papers: Generalised parton distributions at HERA and prosp…

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We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. Our approach follows a previous detailed study of the…

High Energy Physics - Phenomenology · Physics 2009-09-28 Saeed Ahmad , Heli Honkanen , Simonetta Liuti , Swadhin K. Taneja

In the first chapter we give an introduction to hard diffractive scattering in QCD to introduce basic concepts and terminology. In the second chapter we make predictions for the evolution of skewed parton distributions in a proton in the…

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

Generalized parton distributions (GPDs) with purely transverse momentum transfer can be interpreted as Fourier transforms of the distribution of partons in impact parameter space. The helicity-flip GPD $E(x,0,-\Dps)$ is related to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthias Burkardt

Applying arguments based on the operator product expansion for a three-point correlator and relying on quark-hadron duality, we derive an expression for the skewed (non-forward) parton distribution in the pion in the case of a…

High Energy Physics - Phenomenology · Physics 2009-08-25 Alexander P. Bakulev , Rusko Ruskov , Klaus Goeke , N. G. Stefanis

Results from a recent analysis of the zero-skewness generalized parton distributions (GPDs) for valence quarks are discussed. The analysis bases on a physically motivated parameterization of the GPDs with a few free parameters adjusted to…

High Energy Physics - Phenomenology · Physics 2025-01-22 P. Kroll

We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. At \zeta=0, H and E are determined using constraints…

High Energy Physics - Phenomenology · Physics 2017-08-23 S. Ahmad , H. Honkanen , S. Liuti , S. K. Taneja

An approach is proposed to calculate Generalized Parton Distributions (GPDs) in a Constituent Quark Model (CQM) scenario. These off-diagonal distributions are obtained from momentum space wave functions to be evaluated in a given non…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sergio Scopetta , Vicente Vento

The calculation of generalized parton distributions (GPDs) in lattice QCD was traditionally done by calculating matrix elements in the symmetric frame. Recent advancements have significantly reduced computational costs by calculating these…

In the following note, we will present an estimation of the single spin asymmetry in deeply virtual Compton scattering (DVCS) which directly allows one to test predictions of the ratio of the imaginary part of the amplitude in DIS to DVCS,…

High Energy Physics - Phenomenology · Physics 2010-01-06 A. Freund , M. Strikman

We report on the status of the phenomenological access of generalized parton distributions from photon and meson electroproduction off proton. Thereby, we emphasize the role of HERMES data for deeply virtual Compton scattering, which allows…

High Energy Physics - Phenomenology · Physics 2022-03-02 Kresimir Kumericki , Dieter Mueller , Morgan Murray

We have analyzed the beam spin asymmetry and the longitudinally polarized target spin asymmetry of the Deep Virtual Compton Scattering process, recently measured by the Jefferson Lab CLAS collaboration. Our aim is to extract information…

High Energy Physics - Phenomenology · Physics 2014-11-20 M. Guidal

We recall our recent description of quark parton densities of the proton at $Q^2=4 GeV^2$ in terms of Fermi-Dirac distributions parametrized with very few free parameters. We have also proposed some simple assumptions to relate unpolarized…

High Energy Physics - Phenomenology · Physics 2016-09-01 Claude Bourrely , Jacques Soffer

We study the generalized parton distributions (GPDs) of pion for non-zero skewness by considering the leading $| q \bar{q} \rangle$ Fock state component. Inspired from AdS/QCD light-front wave functions, we calculate the pion GPDs. By…

High Energy Physics - Phenomenology · Physics 2018-07-10 Navdeep Kaur , Narinder Kumar , Chandan Mondal , Harleen Dahiya

The nucleon helicity-independent generalized parton distributions (GPDs) of quarks are calculated in the zero skewness case, in the framework of the AdS/QCD model. The present approach is based on a matching procedure of sum rules relating…

High Energy Physics - Phenomenology · Physics 2015-03-17 Alfredo Vega , Ivan Schmidt , Thomas Gutsche , Valery E. Lyubovitskij

The skewing factor, defined as the ratio of the imaginary parts of the amplitudes $Im A(\gamma^* p \to \gamma^* p)/Im A(\gamma^* p \to \gamma p)$ is extracted for the first time from the data using recent Deeply Virtual Compton Scattering…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. Favart , M. V. T. Machado , L. Schoeffel

We present a global analysis program for the generalized parton distributions (GPDs) based on conformal moment expansion. We apply the strategy of universal moment parameterization to fit both the collinear parton distribution functions…

High Energy Physics - Phenomenology · Physics 2022-10-19 Yuxun Guo , Xiangdong Ji , Kyle Shiells

A method is described for calculating the Generalized Parton Distributions (GPDs) of spin 1/2 hadrons made of composite constituents, in an Impulse Approximation framework. GPDs are obtained from the convolution between the light cone…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sergio Scopetta

We summarize recent developments in understanding the concept of generalized parton distributions (GPDs), its relation to nucleon structure, and its application to high-Q2 electroproduction processes. Following a brief review of QCD…

High Energy Physics - Phenomenology · Physics 2009-08-24 C. Weiss

Results from a recent analysis of the zero-skewness generalized parton distributions (GPDs) for valence quarks are reviewed. The analysis bases on a physically motivated parameterization of the GPDs with a few free parameters adjusted to…

High Energy Physics - Phenomenology · Physics 2025-01-22 P. Kroll

We study Generalized Parton Distribution functions (GPDs) usually measured in hard exclusive processes and encoding information on the three dimensional partonic structure of hadrons and their spin decomposition, for non zero skewness…

High Energy Physics - Phenomenology · Physics 2017-06-28 Matteo Rinaldi