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Related papers: Pion-Photon TDAs in the NJL Model

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We consider the problem of construction of a spectral representation for nucleon to meson transition distribution amplitudes (TDAs), non-diagonal matrix elements of nonlocal three quark light-cone operators between a nucleon and a meson…

High Energy Physics - Phenomenology · Physics 2012-06-07 Bernard Pire , Kirill Semenov-Tian-Shansky , Lech Szymanowski

The evaluation of partonic distributions presents a challenge for QCD, and in particular for its Euclidean lattice realization. Recently, objects called quasi-distributions (which become standard distributions in a limit of the longitudinal…

High Energy Physics - Phenomenology · Physics 2017-11-28 Wojciech Broniowski , Enrique Ruiz Arriola

The transition pion-photon form factor is studied within the framework of Light-Cone QCD Sum Rules. The spectral density for the next-to-leading order corrections is calculated for any Gegenbauer harmonic. At the level of the…

High Energy Physics - Phenomenology · Physics 2011-05-13 S. V. Mikhailov , N. G. Stefanis

Nucleon to meson transition distribution amplitudes (TDAs), non-diagonal matrix elements of nonlocal three quark operators between a nucleon and a meson states, arise within the collinear factorized description of hard exclusive…

High Energy Physics - Phenomenology · Physics 2012-01-04 B. Pire , K. Semenov-Tian-Shansky , L. Szymanowski

We investigate the tomographical structure of pion and kaon in light cone quark model (LCQM). In particular, we study the parton distribution amplitude (PDA) of pion and kaon. We obtain the parton distribution function (PDF) and the…

High Energy Physics - Phenomenology · Physics 2020-07-27 Satvir Kaur , Narinder Kumar , Jiangshan Lan , Chandan Mondal , Harleen Dahiya

Leading-twist distribution amplitudes (DAs) of light mesons like pi,rho etc. describe the leading nonperturbative hadronic contributions to exclusive QCD reactions at large energy transfer, for instance electromagnetic form factors. They…

High Energy Physics - Phenomenology · Physics 2009-11-11 Patricia Ball , Angelique Talbot

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

In the present work the Mott effect for pions and kaons is described within a Beth- Uhlenbeck approach on the basis of the PNJL model. The contribution of these degrees of freedom to the thermodynamics is encoded in the temperature…

High Energy Physics - Phenomenology · Physics 2016-03-23 A. Dubinin , D. Blaschke , A. Radzhabov

A global fit to the data from different collaborations (CELLO, CLEO, BaBar) on the pion-photon transition form factor is carried out using light-cone sum rules. The analysis includes the next-to-leading QCD radiative corrections and the…

High Energy Physics - Phenomenology · Physics 2012-01-17 A. P. Bakulev , S. V. Mikhailov , A. V. Pimikov , N. G. Stefanis

The invariant amplitudes for pion electroproduction on the nucleon are evaluated by dispersion relations at constant t with MAID as input for the imaginary parts of these amplitudes. In the threshold region these amplitudes are confronted…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Pasquini , D. Drechsel , L. Tiator

Pion and photo-induced inelastic reactions off protons are studied in a multichannel partial-wave analysis. Properties of nucleon and $\Delta$ resonances are derived and compared to previous analyses. Amplitudes are shown for transitions to…

Nuclear Theory · Physics 2015-06-05 A. V. Anisovich , R. Beck , E. Klempt , V. A. Nikonov , A. V. Sarantsev , U. Thoma

We describe the present status of the pion distribution amplitude (DA) as it originated from several sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates, (ii) an O(\alpha_s) QCD analysis of the CLEO…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. P. Bakulev

An analysis of all available data (CELLO, CLEO, \babar) in the range $[1\div 40]$ GeV$^2$ for the pion-photon transition form factor in terms of light-cone sum rules with next-to-leading-order accuracy is discussed, including twist-four…

High Energy Physics - Phenomenology · Physics 2012-04-24 N. G. Stefanis

We present an extended analysis of the data for the pion-photon transition form factor from different experiments, CELLO, CLEO, and BaBar, and discuss various theoretical approaches which try to reason from them. We focus on the divergent…

High Energy Physics - Phenomenology · Physics 2013-01-03 N. G. Stefanis , Alexander P. Bakulev , S. V. Mikhailov , A. V. Pimikov

We describe the present status of the pion distribution amplitude (DA) as it originates from several sources: (i) a nonperturbative approach based on QCD sum rules with nonlocal condensates, (ii) an $O(\alpha_s)$ QCD analysis of the CLEO…

High Energy Physics - Phenomenology · Physics 2009-04-17 A. P. Bakulev , S. V. Mikhailov , A. V. Pimikov , N. G. Stefanis

The $\gamma^\ast \gamma \to \pi^0$ transition form factor, $G(Q^2)$, is computed on the entire domain of spacelike momenta using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory: the…

We perform a detailed analysis of all existing data (CELLO, CLEO, BaBar) on the pion-photon transition form factor by means of light-cone sum rules in which we include the NLO QCD radiative corrections and the twist-four contributions. The…

High Energy Physics - Phenomenology · Physics 2011-08-29 A. P. Bakulev , S. V. Mikhailov , A. V. Pimikov , N. G. Stefanis

We obtain the distribution amplitude (DA) of the pion from its light-front wave functions in the basis light-front quantization framework. This light-front wave function of the pion is given by the lowest eigenvector of a light-front…

High Energy Physics - Phenomenology · Physics 2021-11-24 Chandan Mondal , Sreeraj Nair , Shaoyang Jia , Xingbo Zhao , James P. Vary

The two-photon-exchange (TPE) effects in the process $e^+e^- \rightarrow \pi^+\pi^-$ at large momentum transfer are discussed within the perturbative QCD (pQCD). The contributions from the twist-2 and twist-3 distribution amplitudes (DAs)…

High Energy Physics - Phenomenology · Physics 2018-09-12 Hong-Yu Chen , Hai-Qing Zhou

We describe the present status of the pion distribution amplitude as originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates, and (ii) a NLO QCD analysis of the CLEO data on…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. P. Bakulev