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Related papers: Confinement and cut-off: a model for the pion quar…

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An overview of the vector and tensor Generalized Parton Distributions for a charged pion is presented. Such observables, belonging to the set of quantities fundamental for a detailed investigation of the hadronic inner dynamics, have been…

High Energy Physics - Phenomenology · Physics 2015-06-11 Giovanni Salme' , Emanuele Pace , Giovanni Romanelli

After discussing some hints for possible masses of quasiparticles in quark matter on the basis of lattice equation of state, we present pion and kaon transverse spectra obtained by recombining quarks with distributed mass and thermal cut…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. S. Biro , K. Urmossy , G. G. Barnafoldi

We give a brief review of the theoretical description of low energy pion-pion scattering by the combined use of Chiral Perturbation Theory and Roy equations, an update of the Regge parametrization of $\pi\pi$ cross sections at high…

High Energy Physics - Phenomenology · Physics 2010-11-05 Irinel Caprini , Gilberto Colangelo , Heinrich Leutwyler

We discuss a general diagrammatic description of n-point functions in the QCD instanton vacuum that resums planar diagrams, enforces gauge invariance and spontaneously broken chiral symmetry. We use these diagrammatic rules to derive the…

High Energy Physics - Phenomenology · Physics 2020-07-29 Arthur Kock , Yizhuang Liu , Ismail Zahed

Elastic pion-pion and pion-nucleon scattering are reviewed in the context of chiral perturbation theory. Theoretical results from systematic low-energy expansions to O(p^6) for pion-pion and to O(p^3) for pion-nucleon scattering are…

High Energy Physics - Phenomenology · Physics 2009-10-30 Gerhard Ecker

A coherent state of pions is introduced to the nonrelativistic quark model. The coherent pair approximation is employed for the pion field in order to maintain the spin-isospin symmetry. In this approximation the pion is localized in the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Masanori Morishita , Masaki Arima

We recalculated pion virtual Compton scattering in perturbative QCD in this paper. Our calculation avoids some deficiencies in existing literatures, and treats real Compton scattering as a limit case in which the mass of the virtual photon…

High Energy Physics - Phenomenology · Physics 2015-06-25 Ding-fang Zeng , Bo-qiang Ma

Resonance production and decay into pion pairs is simulated in a non-extensive quark matter with multi-particle interactions. Final state pion spectra are found to take the form of the Tsallis distribution, in accordance with measurements.…

High Energy Physics - Phenomenology · Physics 2017-08-23 Karoly Urmossy , Tamas S. Biro , Gergely G. Barnaföldi

We discuss a constraint of conformal symmetry in the analysis of the pion form factor. The usual power-law behavior of the form factor obtained in the perturbative QCD analysis can also be attained by taking negligible quark masses in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. -M. Choi , C. -R. Ji

Form factors for pions interactions with constituent quarks are investigated as the leading effective couplings obtained from a one loop background field method applied to a global color model. Two pion field definitions are considered and…

High Energy Physics - Phenomenology · Physics 2023-03-27 Fabio L. Braghin

The elementary fragmentation function that describes the process $q\to \pi$ is predicted applying crossing and charge symmetry to the cut diagram of the pion valence quark distribution function. This elementary probability distribution…

High Energy Physics - Phenomenology · Physics 2025-06-23 Roberto Correa da Silveira , Fernando E. Serna , Bruno El-Bennich

We study baryon spectroscopy including the effects of pseudoscalar meson exchange and one gluon exchange potentials between quarks, governed by $\alpha_s$. The non-perturbative, hyperspherical method calculations show that one can obtain a…

Nuclear Theory · Physics 2008-11-26 Z. Dziembowski , M. Fabre de la Ripelle , Gerald A. Miller

The b1 structure function is an observable feature of a spin-1 system sensitive to non-nucleonic components of the target nuclear wave function. The contributions of exchanged pions in the deuteron are estimated and found to be of…

Nuclear Theory · Physics 2014-04-23 Gerald A. Miller

A flavor SU(2) effective model for pions and quarks is derived by considering polarization effects departing from the usual quark-quark effective interaction induced by dressed gluon exchange, i.e. a global color model for QCD. For that,…

High Energy Physics - Phenomenology · Physics 2016-05-30 Fabio L. Braghin

From a refined non-relativistic quark model that fits the baryonic low-energy spectrum the study of strong pion decay processes within an elementary emission model scheme points out the need of incorporating size-contributing components…

Nuclear Theory · Physics 2009-10-30 F. Cano , P. González , S. Noguera , B. Desplanques

A rainbow-ladder truncation of QCD's Dyson-Schwinger equations, constrained by existing applications to hadron physics, is employed to compute the valence-quark parton distribution functions of the pion and kaon. Comparison is made to pi-N…

Nuclear Theory · Physics 2011-07-04 Trang Nguyen , Adnan Bashir , Craig D. Roberts , Peter C. Tandy

We relate ordinary and skewed parton distributions to soft overlap contributions to elastic form factors and large angle Compton scattering, using light-cone wave functions in a Fock state expansion of the nucleon. With a simple ansatz for…

High Energy Physics - Phenomenology · Physics 2011-09-13 M. Diehl , T. Feldmann , R. Jakob , P. Kroll

We consider an alternative explanation of newly found growth of neutral pion transition form factor with virtuality of one of photon. It is based on Sudakov suppression of quark-photon vertex. Some applications to scattering and…

High Energy Physics - Phenomenology · Physics 2011-03-31 E. A. Kuraev , A. N. Ilyichev , V. V. Bytev , Yu. M. Bystritskiy

A microscopic model for the $N\bar N\to\pi\pi$ process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical information. The scalar ($\sigma$) and vector ($\rho$) piece of…

Nuclear Theory · Physics 2009-09-25 C. Schütz , J. W. Durso , K. Holinde , B. C. Pearce , J. Speth

We present a method which allows to extract theoretical informations out of a limited set of experimental data and observables, forming up in general an under- constrained system. It has been applied to the field of nucleon structure, in…

High Energy Physics - Phenomenology · Physics 2015-06-23 Marie Boër , Michel Guidal