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Related papers: Pion-Photon TDAs in the NJL Model

200 papers

The finite temperature phase transition of strongly interacting matter is studied within a nonlocal chiral quark model of the NJL type coupled to a Polyakov loop. In contrast to previous investigations which were restricted to the…

High Energy Physics - Phenomenology · Physics 2008-12-18 D. Blaschke , M. Buballa , A. E. Radzhabov , M. K. Volkov

This is a short presentation of the results for the pion-nucleon distribution amplitudes which are expressed in terms of the nucleon distribution amplitudes with the help of current algebra. Everything is considered to be at threshold.

High Energy Physics - Phenomenology · Physics 2017-08-23 Andreas Peters

We extract constraints on the pion distribution amplitude from available data on the pion-photon transition form factor in the framework of light-cone sum rules. A pronounced discrepancy $(2.7-3)\sigma$ between the Gegenbauer expansion…

High Energy Physics - Phenomenology · Physics 2015-06-11 A. V. Pimikov , A. P. Bakulev , S. V. Mikhailov , N. G. Stefanis

The pion-nucleon amplitude is considered in the vicinity of the elastic scattering threshold within a relativistic dynamical model dressing the pi N N and pi N Delta vertices self-consistently with an infinite number of meson loops. The…

Nuclear Theory · Physics 2009-11-07 S. Kondratyuk

We discuss the relevance of a dedicated measurement of exclusive production of a pair of neutral pions in a hard gamma* gamma scattering at small momentum transfer. In this case, the virtuality of one photon provides us with a hard scale in…

High Energy Physics - Phenomenology · Physics 2009-07-21 J. P. Lansberg , B. Pire , L. Szymanowski

This talk presents issues pertaining to the quark structure of the pion within QCD, both from the theoretical and from the experimental point of view. We review and discuss the pion-photon transition form factor and the pion's…

High Energy Physics - Phenomenology · Physics 2008-11-07 N. G. Stefanis

The pion-nucleon scattering is investigated by using several three-dimensional reduction schemes of the Bethe-Salpeter equation for a model Lagrangian involving $\pi$, $N$, $\Delta$, $\rho$, and $\sigma$ fields. It is found that all of the…

Nuclear Theory · Physics 2009-11-07 Cheng-Tsung Hung , Shin Nan Yang , T. -S. H. Lee

We give predictions for the partial wave amplitudes of pion photoproduction near threshold by means of dispersion relations at fixed t. The free parameters of this approach are determined by a fit to experimental data in the energy range…

Nuclear Theory · Physics 2016-09-08 O. Hanstein , D. Drechsel , L. Tiator

We calculate generalized parton distribution functions in a field theoretic formalism using a covariant Bethe-Salpeter approach for the determination of the bound-state wave function. We describe the procedure in an exact calculation in…

Nuclear Theory · Physics 2011-10-11 S. Noguera , L. Theussl , V. Vento

We study the exclusive production of pi-pi and rho-pi in hard gamma* gamma scattering in the forward kinematical region where the virtuality of one photon provides us with a hard scale in the process. The newly introduced concept of…

High Energy Physics - Phenomenology · Physics 2008-12-18 J. P. Lansberg , B. Pire , L. Szymanowski

We review the potentialities offered by the study of backward exclusive processes in a new scaling regime, i.e. involving a large -timelike or spacelike- Q2 photon and a baryonic exchange in the t-channel. We recall the concept of…

High Energy Physics - Phenomenology · Physics 2010-11-16 J. P. Lansberg , B. Pire , L. Szymanowski

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 provide the definition of the complete set of light-cone distribution amplitudes (LCDAs) for the ground state heavy bottom baryons with the spin-parities J^P = 1/2^+ and J^P = 3/2^+ in the heavy quark limit. We present the…

High Energy Physics - Phenomenology · Physics 2015-06-12 A. Ali , C. Hambrock , A. Ya. Parkhomenko , Wei Wang

The CLEO experimental data on the $\pi\gamma$ transition are analyzed to next-to-leading order accuracy in QCD perturbation theory using light-cone QCD sum rules. By processing these data along the lines proposed by Schmedding and Yakovlev,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexander P. Bakulev , S. V. Mikhailov , N. G. Stefanis

We analyse pion-nucleus reactions in a microscopic transport model of the BUU type, which propagates nucleons, pions, deltas and N(1440)-resonances explicitly in space and time. In particular we examine pion absorption and inelastic…

Nuclear Theory · Physics 2009-10-22 A. Engel , W. Cassing , U. Mosel , M. Schäfer , Gy. Wolf

Low and high energy properties of the pion are reviewed in the framework of chiral quark models. Particular emphasis is put on the simplest version of the SU(2) NJL model as prototype. The role of gauge invariance in this kind of…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Ruiz Arriola

We discuss the evaluation of the transition form factor (TFF) $F^{\gamma*\gamma\pi^0}(Q^2)$ by means of QCD theory and by state-space reconstruction from topological data analysis. We first calculate this quantity in terms of quark-gluon…

High Energy Physics - Phenomenology · Physics 2019-06-21 N. G. Stefanis

We study the phase diagram and the pion modes in the electrically neutral two flavor PNJL model. One of the main result of this paper is that when electrical neutrality is required, pions do not condense in the ground state of the model:…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. Abuki , M. Ciminale , R. Gatto , N. D. Ippolito , G. Nardulli , M. Ruggieri

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

The dichotomy of the pion as QCD's Goldstone mode and a bound state of massive constituents is easily understood using the Dyson-Schwinger equations. That provides the foundation for an efficacious phenomenology, which correlates the pion's…

Nuclear Theory · Physics 2010-03-04 M. B. Hecht , C. D. Roberts