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Related papers: Shape of Pion Distribution Amplitude

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We present an improved calculation on the pionic twist-3 distribution amplitudes $\phi^{\pi}_{p}$ and $\phi^{\pi}_{\sigma}$, which are studied within the QCD sum rules. By adding all the uncertainties in quadrature, it is found that…

High Energy Physics - Phenomenology · Physics 2011-02-18 Tao Zhong , Xing-Gang Wu , Jia-Wei Zhang , Yun-Qing Tang , Zhen-Yun Fang

It has been pointed out that the recent BaBar data on the pi gamma^* -> gamma transition form factor F_{pi gamma}(Q^2) at low (high) momentum transfer squared Q^2 indicate an asymptotic (flat) pion distribution amplitude. These seemingly…

High Energy Physics - Phenomenology · Physics 2009-11-05 Hsiang-nan Li , Satoshi Mishima

It is believed that one can extract more accurate information of the pion distribution amplitude from the pion-photon transition form factor (TFF) due to the single pion in this process. However the BABAR and Belle data of the pion-photon…

High Energy Physics - Phenomenology · Physics 2013-04-01 Tao Huang , Xing-Gang Wu , Tao Zhong

We calculate the two-pion light-cone distribution amplitudes in the effective low-energy theory based on the instanton vacuum. These generalized distribution amplitudes describe the soft (non-perturbative) part of the process…

High Energy Physics - Phenomenology · Physics 2009-12-30 M. V. Polyakov , C. Weiss

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

We account for dynamical spin effects in the holographic light-front wavefunction of the pion in order to predict its mean charge radius, decay constant, spacelike electromagnetic form factor, twist-2 Distribution Amplitude and the…

High Energy Physics - Phenomenology · Physics 2017-04-12 Mohammad Ahmady , Farrukh Chishtie , Ruben Sandapen

We project onto the light-front the pion's Poincare'-covariant Bethe-Salpeter wave-function, obtained using two different approximations to the kernels of QCD's Dyson-Schwinger equations. At an hadronic scale both computed results are…

Nuclear Theory · Physics 2015-06-12 Lei Chang , I. C. Cloet , J. J. Cobos-Martinez , C. D. Roberts , S. M. Schmidt , P. C. Tandy

We present an improved analysis of the constraints on the first two Gegenbauer moments, $a^\pi_2$ and $a^\pi_4$, of the pion's leading-twist distribution amplitude from a QCD light-cone sum rule analysis of $B\to\pi$ weak transition form…

High Energy Physics - Phenomenology · Physics 2008-12-18 Xing-Gang Wu

The pseudoscalar projection of the pion's Poincare'-covariant Bethe-Salpeter amplitude onto the light-front may be understood to provide the probability distribution of the chiral condensate within the pion. Unlike the parton distribution…

Nuclear Theory · Physics 2015-06-17 Lei Chang , Craig D. Roberts , Sebastian M. Schmidt

The exclusive production of \pi\pi and \pi\rho in hard \gamma^{\star}\gamma scattering in the forward kinematical region where the virtual photon is highly off-shell are studied through the \gamma\to\pi^- Transition Distribution Amplitudes.…

High Energy Physics - Phenomenology · Physics 2009-03-31 A. Courtoy , S. Noguera

The pion structure function is investigated in a simple model, where the pion and its constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi -> gamma* pi scattering…

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

The light-cone wave function of the pion is calculated within the Nambu-Jona-Lasinio model. The result is used to derive the pion electromagnetic form factor, charge radius, structure function, pi-gamma transition form factor and…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Heinzl

Recent BaBaR data on the pion transition form factor, whose Q^2 dependence is much steeper then predicted by asymptotic Quantum Chromodynamics (QCD), have caused a renewed interest in its theoretical description. We present here a formalism…

High Energy Physics - Phenomenology · Physics 2010-12-09 S. Noguera , V. Vento

We propose a new method to obtain the K -> pi pi amplitude from K -> pi which allows one to fully account for the effects of final state interactions. The method is based on a set of dispersion relations for the K -> pi pi amplitude in…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Buechler , G. Colangelo , J. Kambor , F. Orellana

We propose a new method to obtain the K -> pi pi amplitude from K -> pi which allows one to fully account for the effects of final state interactions. The method is based on a set of dispersion relations for the K -> pi pi amplitude in…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Buchler

We extend our analysis of quasi-distributions onto the pion distribution amplitude. Using the formalism of parton virtuality distribution amplitudes (VDAs), we establish a connection between the pion transverse momentum dependent…

High Energy Physics - Phenomenology · Physics 2017-04-05 Anatoly V. Radyushkin

In the present paper, we study the properties of $\phi$-meson longitudinal leading-twist light-cone distribution amplitude $\phi_{2;{\phi}}^{\|}(x,\mu)$ by starting from a light-cone harmonic oscillator model for its wavefunction. To fix…

High Energy Physics - Phenomenology · Physics 2024-03-18 Dan-Dan Hu , Xing-Gang Wu , Long Zeng , Hai-Bing Fu , Tao Zhong

We study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of…

High Energy Physics - Phenomenology · Physics 2023-07-26 Jian Chai , Shan Cheng , Jun Hua

We consider pion pair production in two-photon collisions, gamma* gamma -> pi+ pi-, at large photon virtuality Q^2 and center-of-mass energy \sqrt{s} in the hard-scattering picture. In the limit where s is large but s << Q^2 we derive an…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Diehl , Th. Feldmann , P. Kroll , C. Vogt

We calculated the first two moments of the light-cone distribution amplitudes for the pseudoscalar mesons ($\pi$ and $K$) and the longitudinally polarised vector mesons ($\rho$, $K^*$ and $\phi$) as part of the UKQCD and RBC collaborations'…

High Energy Physics - Lattice · Physics 2010-11-15 R. Arthur , P. A. Boyle , D. Brömmel , M. A. Donnellan , J. M. Flynn , A. Jüttner , H. Pedroso de Lima , T. D. Rae , C. T. Sachrajda , B. Samways