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Related papers: Pion-Nucleon Distribution Amplitudes

200 papers

An explicitly crossing-symmetric decomposition of the pion-pion scattering amplitudes into low- and high-energy components is established. The high-energy components are entirely determined by absorptive parts at high energies. With the…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Wanders

We review the structure of Roy-Steiner equations for pion-nucleon scattering, the solution for the partial waves of the t-channel process $\pi\pi\to \bar N N$, as well as the high-accuracy extraction of the pion-nucleon S-wave scattering…

High Energy Physics - Phenomenology · Physics 2016-03-24 Martin Hoferichter , Jacobo Ruiz de Elvira , Bastian Kubis , Ulf-G. Meißner

We show that processes involving pions that remain very near their mass-shell can be reliably computed in the pionless effective field theory, with the pion integrated in as a heavy field. As an application, we compute the pion-deuteron…

Nuclear Theory · Physics 2009-11-07 Silas R. Beane , Martin J. Savage

We present and apply a novel scheme for studying photon- and pion-nucleon scattering beyond the threshold region. Partial-wave amplitudes for the $\gamma\, N$ and $\pi N$ states are obtained by an analytic extrapolation of subthreshold…

High Energy Physics - Phenomenology · Physics 2015-03-13 A. Gasparyan , M. F. M. Lutz

Pion-photoproduction data is examined to check for the nucleon-helicity conservation predicted by asymptotic QCD. The differential cross section shows agreement with constituent-counting rules, and polarization data is not in disagreement…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. A. Jenkins , I. I. Strakovsky

We review the status of our understanding of nucleon structure based on the modelling of different kinds of parton distributions. We use the concept of generalized transverse momentum dependent parton distributions and Wigner distributions,…

High Energy Physics - Phenomenology · Physics 2016-07-20 M. Burkardt , B. Pasquini

A new theoretical framework is proposed for the description of baryon light-cone distribution amplitudes, based on the observation that their scale dependence to leading logarithmic accuracy is described by a completely integrable model.…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. M. Braun

In this paper we study the gluon distribution functions in nucleons and pions at a low resolution $Q^2$ scale. This is an important issue since parton densities at low $Q^2$ have always been taken as an external input which is adjusted…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. R. Christiansen , J. Magnin

We review recent progress in calculating the twist--2 parton distribution functions at a low normalization point in the large--$N_c$ limit, where the nucleon can be described as a soliton of the effective chiral lagrangian. This…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Weiss

The present status of neutrino cross section physics is reviewed focusing on the recent theoretical developments in quasielastic scattering, multi-nucleon contributions to the inclusive scattering and pion production on nucleons and nuclei.…

High Energy Physics - Phenomenology · Physics 2016-05-17 Luis Alvarez-Ruso

We calculate the nucleon-nucleon scattering amplitudes in the 1S0 and 3S1-3D1 channels at next-to-next to leading order starting from a recently proposed non-relativistic chiral effective theory, which includes dibaryon fields as…

Nuclear Theory · Physics 2010-04-06 Joan Soto , Jaume Tarrus

The new BABAR data on the pion-photon transition form factor arouses people's new interests on the determination of pion distribution amplitude. To explain the data, we take both the leading valence quark state's and the non-valence quark…

High Energy Physics - Phenomenology · Physics 2015-03-17 Xing-Gang Wu , Tao Huang

The amplitudes of the pion electroproduction from the nucleon are derived up to third order in the chiral effective theory including explicit $\Delta$(1232) >. The Q^2 evolutions of weighted integrals of amplitudes are presented.

Nuclear Theory · Physics 2007-05-23 Chung Wen Kao

We construct the complete effective chiral pion-nucleon Lagrangian to third order in small momenta based on relativistic chiral perturbation theory. We then perform the so-called heavy baryon limit and construct all terms…

High Energy Physics - Phenomenology · Physics 2009-10-31 Nadia Fettes , Ulf-G. Meißner , Sven Steininger

A forward dispersion calculation is implemented for the spin polarizabilities $\gamma_1, ... ,\gamma_4$ of the proton and the neutron. These polarizabilities are related to the spin structure of the nucleon at low energies and are…

Nuclear Theory · Physics 2009-10-30 D. Drechsel , G. Krein , O. Hanstein

We present here an extension of our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward gamma^* pi -> gamma^* pi scattering amplitude is…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. Lansberg , F. Bissey , J. R. Cudell , J. Cugnon , P. Stassart

In the first part of the talk, I discussed the nature of the effective theory that describes the properties of the pion-nucleon-interaction at low energies, using the static model as a starting point. In the second part, I then pointed out…

High Energy Physics - Phenomenology · Physics 2011-04-15 H. Leutwyler

Parton distributions for the pion are studied in a chiral quark model characterized by a quark propagator for which a spectral representation is assumed. Electromagnetic and chiral symmetry constraints are imposed through the relevant…

High Energy Physics - Phenomenology · Physics 2017-08-23 E. Ruiz Arriola

We present a dispersion relation in the pion-mass squared, which static quantities (nucleon mass, magnetic moment, etc.) obey under the assumption of analyticity in the entire complex $m_\pi^2$ plane modulo a cut at negative $m_\pi^2$…

High Energy Physics - Phenomenology · Physics 2014-11-20 Tim Ledwig , Vladimir Pascalutsa , Marc Vanderhaeghen

I present an overview of some current topics in the measurement of Parton Distribution Functions.

High Energy Physics - Phenomenology · Physics 2015-06-25 Jon Pumplin