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Related papers: Pion-Nucleon Distribution Amplitudes

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We consider two-nucleon scattering close to threshold. Partial-wave amplitudes are obtained by an analytic extrapolation of subthreshold reaction amplitudes calculated in a relativistic formulation of chiral perturbation theory. The…

Nuclear Theory · Physics 2015-06-12 A. M. Gasparyan , M. F. M. Lutz , E. Epelbaum

We review the major progress of the past decade concerning our understanding of the nucleon-nucleon interaction. The focus is on the low-energy region (below pion production threshold), but a brief outlook towards higher energies is also…

Nuclear Theory · Physics 2009-11-07 R. Machleidt , I. Slaus

A scenario is investigated in which the leading-twist pion distribution amplitude phi_pi (x) is approximated by the pion decay constant f_pi for all essential values of the light-cone fraction x. A model for the light-front wave function…

High Energy Physics - Phenomenology · Physics 2014-11-20 A. V. Radyushkin

The generalized parton distributions and the generalized distribution amplitudes give access to a deeper understanding of the quark and gluon content of hadrons. In this short review, we select some new developments of their interesting…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. Pire

A short review of the present knowledge of the nucleons distribution in nuclei is given. A proposal is made about a possible measurements of the neutron distribution through polarized electron scattering off nuclei.

Nuclear Theory · Physics 2007-05-23 W. M. Alberico , A. Molinari

Many approaches to nucleon-nucleus elastic and inelastic scattering are based on the use of the free-space nucleon-nucleon transition amplitude. In calculations where the full spin-dependence of this amplitude is needed, its use is more…

Nuclear Theory · Physics 2009-11-07 R. Crespo , A. M. Moro

We discuss what can be learned about the shape of the pion distribution amplitude from the form factor for gamma* gamma(*) to pi transitions.

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

Using a self-consistent delta-hole model the pion propagation in isospin asymmetric nuclear matter is studied. In neutron-rich matter, corresponding to heavy nuclei, a significant difference in positive and negative pion light-cone…

Nuclear Theory · Physics 2015-06-26 C. L. Korpa , A. E. L. Dieperink

Pion photoproduction amplitudes are calculated from a set of equations that have been derived by coupling an external photon to all places in a dressed pion-nucleon vertex. The calculation is consistent with gauge invariance, charge…

Nuclear Theory · Physics 2019-03-13 T. Skawronski , B. Blankleider , A. N. Kvinikhidze

To study cross sections and polarization asymmetries for the processes $e p \to e n \pi^+$ and $e p \to e p \pi^0$ in the backward region, we develop a flexible phenomenological model for nucleon-to-pion transition distribution amplitudes…

High Energy Physics - Phenomenology · Physics 2025-11-03 Bernard Pire , Kirill Semenov-Tian-Shansky , Paweł Sznajder , Lech Szymanowski

I review the current status of global analysis of nuclear parton distributions and discuss some near-future prospects. I also advocate proton-nucleus (p-$A$) measurements at the LHC with $A\ll 208$ from the viewpoint of nuclear parton…

High Energy Physics - Phenomenology · Physics 2018-12-03 Hannu Paukkunen

The extraction of the isovector s-wave pi N amplitude from pionic atoms is studied with special emphasis on uncertainties and their dependence on the assumptions made regarding the neutron density distributions in nuclei and on the size of…

Nuclear Theory · Physics 2009-11-10 E. Friedman , A. Gal

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

We study pion--nucleon scattering with a chiral lagrangian of pions, nucleons, and $\Delta$-isobars. The scattering amplitude is evaluated to one-loop $Q^3$ order, where $Q$ is a generic small momentum, using a new approach which is…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paul J. Ellis , Hua-Bin Tang

We give an overview of the theory for generalized parton distributions. Topics covered are their general properties and physical interpretation, the possibility to explore the three-dimensional structure of hadrons at parton level, their…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Diehl

Generalized Parton Distributions of the pion are evaluated in chiral quark models with the help of double distributions. As a result the polynomiality conditions are automatically satisfied. In addition, positivity constraints, proper…

High Energy Physics - Phenomenology · Physics 2009-11-13 Wojciech Broniowski , Enrique Ruiz Arriola , Krzysztof Golec-Biernat

We derive an explicit and model-independent representation for the skewed quark distribution of the pion in the limit of large momentum transfer. Our result is expressed in terms of the conventional pion distribution amplitudes and complies…

High Energy Physics - Phenomenology · Physics 2014-11-17 C. Vogt

A general expression for the $\pi -N$ and $\pi-\Delta $ scattering lengths is derived in the framework of a microscopic calculation. Annihilation, negative energy wave-functions and spontaneous chiral symmetry are included consistently. The…

Nuclear Theory · Physics 2009-11-07 Pedro Bicudo , Manuel Faria , Gonçalo Marques , J. Emilio Ribeiro

We present an extensive study on generalized parton distributions of pions. In particular, we present the results for the pion-photon transition distribution amplitudes in the Nambu - Jona-Lasinio model. We discuss the phenomenology of such…

High Energy Physics - Phenomenology · Physics 2010-10-15 A. Courtoy

Recent experimental results on the proton and neutron polarizabilities are examined from the point of view of backward dispersion relations. Results are found to be in reasonable agreement with the measured values. A rigorous relationship…

High Energy Physics - Phenomenology · Physics 2011-07-19 Barry R. Holstein , A. M. Nathan