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Related papers: Two-Pion Exchange in proton-proton Scattering

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Taking into account PDFs obtained by various Collaborations, the momentum transfer dependence of GPDs of the pion are obtained. The calculated electromagnetic and gravitomagnetic form factors of the pions and nucleons are used for the…

High Energy Physics - Phenomenology · Physics 2020-01-29 O. V. Selyugin

We study the non-forward matrix elements of twist-2 QCD light-ray operators and their representations in terms of skewed and double distributions, considering the pion as well as the nucleon. We point out the importance of explicitly…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. V. Polyakov , C. Weiss

We examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and the $\bar{d}-\bar{u}$ flavor asymmetry in the proton. A detailed $\chi^2$ analysis of the ZEUS and H1 cross sections,…

High Energy Physics - Phenomenology · Physics 2016-03-23 J. R. McKenney , Nobuo Sato , W. Melnitchouk , Chueng-Ryong Ji

The nucleon-nucleon scattering in a large magnetic background is considered to find its potential to change the neutrino emissivity of the neutron stars. For this purpose we consider the one-pion-exchange approximation to find the NN…

High Energy Physics - Phenomenology · Physics 2010-12-09 E. Bavarsad , M. Haghighat , R. Mohammadi

We investigate the parity-violating nucleon-nucleon potential as obtained in chiral effective field theory. By using resonance saturation we compare the chiral potential to the more traditional one-meson exchange potential. In particular,…

Nuclear Theory · Physics 2014-07-17 J. de Vries , N. Li , Ulf-G. Meißner , N. Kaiser , X. -H. Liu , S. -L. Zhu

Three-nucleon forces have been considered to be one possibility to resolve the well known discrepancy between experimental values and theoretical calculations of the nucleon analyzing power in low energy nucleon-deuteron scattering. In this…

Nuclear Theory · Physics 2009-10-31 S. Ishikawa

Dilepton production in proton-proton collision through $\gamma\gamma$-fusion with one proton scattered elastically while the second produces a hadron jet is considered. Semi-analytical formulas describing the cross section of a muon pair…

High Energy Physics - Phenomenology · Physics 2022-01-26 S. I. Godunov , E. K. Karkaryan , V. A. Novikov , A. N. Rozanov , M. I. Vysotsky , E. V. Zhemchugov

We evaluate the two--pion contribution to the nucleon electromagnetic form factors by use of dispersion analysis and chiral perturbation theory. After subtraction of the rho--meson component, we calculate the distributions of charge and…

High Energy Physics - Phenomenology · Physics 2009-11-10 H. -W. Hammer , D. Drechsel , Ulf-G. Meißner

Motivated by the 1/Nc expansion, we present a simple model of pion-pion scattering as a sum of a `current-algebra' contact term and resonant pole exchanges. The model preserves crossing symmetry as well as unitarity up to 1.2 GeV. Key…

High Energy Physics - Phenomenology · Physics 2008-11-26 Masayasu Harada , Francesco Sannino , Joseph Schechter

We use a recently developed dispersive approach to compute the two-photon exchange (TPE) correction to elastic electron-proton scattering, including contributions from hadronic $J^P=1/2^\pm$ and $3/2^\pm$ resonant intermediate states…

Nuclear Theory · Physics 2020-11-04 Jaseer Ahmed , P. G. Blunden , W. Melnitchouk

We give a compact expression for the unpolarised differential cross section for muon-proton scattering in the one photon exchange approximation. The effect of adding the vacuum polarisation amplitude to the no-spin-flip amplitude for one…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Gashi , G. Rasche , W. S. Woolcock

A chiral pion-nucleon amplitude supplemented by the HJS subthreshold coefficients is used to calculate the the long range part of the two-pion exchange nucleon-nucleon potential. In our expressions the HJS coefficients factor out, allowing…

Nuclear Theory · Physics 2009-10-30 Manoel R. Robilotta , Carlos A. da Rocha

The nucleon distribution amplitudes and the nucleon-to-pion transition distribution amplitudes are investigated at leading twist within the frame of a light-cone quark model. The distribution amplitudes probe the three-quark component of…

High Energy Physics - Phenomenology · Physics 2010-05-28 B. Pasquini , M. Pincetti , S. Boffi

We investigate the dispersive contribution by radiative processes such as (pi- proton to neutron gamma) and (pi- proton to Delta gamma) to the pion-nucleon scattering lengths of charged pions in the heavy baryon limit. They give a large…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. E. O. Ericson , A. N. Ivanov

We study the pp \to pp\pi^0 reaction near threshold based on heavy-baryon chiral perturbation theory. We show that the two-pion-exchange diagrams give much larger contribution than the one-pion-exchange diagram which is of lower chiral…

Nuclear Theory · Physics 2008-11-26 F. Myhrer

We propose possible methods to measure the nucleon electromagnetic form factors in presence of two-photon exchange. Using a general parametrization of the spin structure of the matrix element for elastic $eN$-scattering, in terms of three…

Nuclear Theory · Physics 2009-11-10 M. P. Rekalo , E. Tomasi-Gustafsson

Nuclear corrections are presented for neutrino and electron induced reactions in a pedagogical manner. The formalism is demonstrated with numerical studies and is shown to produce substantial corrections in channels where the pions have the…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. A. Paschos , I. Schienbein , J. Y. Yu

A detailed discussion of the long-range one-pion exchange (Yukawa potential) contribution to the 2S hyperfine splitting in muonic hydrogen which had, until recently, been disregarded is presented. We evaluate the relevant vertex amplitudes,…

High Energy Physics - Phenomenology · Physics 2016-06-15 Nguyen Thu Huong , Emi Kou , Bachir Moussallam

Dispersion relations provide a powerful tool to analyse the electromagnetic form factors of the nucleon both in the space-like and time-like regions with constraints from other experiments, unitarity, and perturbative QCD. We give a brief…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. -W. Hammer

We study the effects of gluon saturation on pion production in high energy proton-nucleus collisions using the color glass condensate model. At high p_perp, we show that the p_perp-distribution of gluons behaves as ~ 1/(p_perp^7) in…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. T. Lenaghan , K. Tuominen