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Related papers: Tagging the pion quark structure in QCD

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We present a systematic study of twist three light-cone distribution amplitudes of vector mesons in QCD, which is based on conformal expansion and takes into account meson and quark mass corrections. A complete set of distribution…

High Energy Physics - Phenomenology · Physics 2010-01-07 Patricia Ball , V. M. Braun , Y. Koike , K. Tanaka

Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…

High Energy Physics - Lattice · Physics 2018-04-18 Jonna Koponen , André Zimermmane-Santos , Christine Davies , G. Peter Lepage , Andrew Lytle

We present a systematic study of twist-4 light-cone distribution amplitudes of vector mesons in QCD, which is based on conformal expansion. The structure of meson mass corrections is studied in detail. A complete set of distribution…

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

We investigate the twist-$3$ transverse-momentum-dependent parton distribution functions (TMDs) of the pion with basis light-front quantization. The twist-3 TMDs are not independent and can be decomposed into twist-$2$ and genuine twist-$3$…

High Energy Physics - Phenomenology · Physics 2023-04-12 Zhimin Zhu , Zhi Hu , Jiangshan Lan , Chandan Mondal , Xingbo Zhao , James P. Vary , BLFQ Collaboration

In this lattice QCD study we evaluate the nucleon spin decomposition to quarks and gluons contributions. We employ one gauge ensemble of maximally twisted mass fermions with two degenerate light quarks tuned to approximately reproduce the…

We use phenomenological nonlocal Lagrangians, which lead to non trivial forms for the quark propagator, to describe the pion. We define a procedure, based on the Dyson-Schwinger equations, for the calculation of the pion parton…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Noguera , V. Vento

Using new experimental data on the leptonic mass spectrum of B->pi l nu, we simultaneously determine |V_ub| and constrain a_2^pi and a_4^pi, the first two Gegenbauer moments of the pion's leading-twist distribution amplitude. We find |V_ub|…

High Energy Physics - Phenomenology · Physics 2010-01-15 Patricia Ball , Roman Zwicky

We present a systematic study of twist-3 light-cone distribution amplitudes of $K^*$ and $\phi$ mesons in QCD. The structure of SU(3)-breaking corrections is studied in detail. Non-perturbative input parameters are estimated from QCD sum…

High Energy Physics - Phenomenology · Physics 2010-10-27 Patricia Ball , G. W. Jones

Within the framework of the conventional QCD sum rules, we study the pion two-point correlation function, $i\int d^4x e^{iq\cdot x} < 0| T J_N(x) {\bar J}_N(0)|\pi(p)>$, beyond the soft-pion limit. We construct sum rules from the three…

Nuclear Theory · Physics 2009-10-31 Hungchong Kim , Su Houng Lee , Makoto Oka

A model for the twist-3 wave function $\psi_p(x,\mathbf{k_\perp})$ of the pion has been constructed based on the moment calculation by applying the QCD sum rules, whose distribution amplitude has a better end-point behavior than that of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tao Huang , Xing-Gang Wu

The leading twist parametrization of dipion mass distribution in hard exclusive reactions is proposed. Its parameters are related to quark distributions (usual and skewed) in the pion and to distributions amplitudes of mesons ($\pi$,…

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

We calculate the two-point massless QCD correlator of nonlocal (composite) vector quark currents with chains of fermion one-loop radiative corrections inserted into gluon lines. The correlator depends on the Bjorken fraction $x$ related to…

High Energy Physics - Phenomenology · Physics 2023-11-08 S. V. Mikhailov , N. Volchanskiy

We continue the program [1] of carving out the space of large $N$ confining gauge theories by modern S-matrix bootstrap methods, with the ultimate goal of cornering large $N$ QCD. In this paper, we focus on the effective field theory of…

High Energy Physics - Theory · Physics 2023-07-06 Jan Albert , Leonardo Rastelli

We study the pion Distribution Amplitude (\pi DA) in the context of a nonlocal chiral quark model. The corresponding Lagrangian reproduces the phenomenological values of the pion mass and decay constant, as well as the momentum dependence…

High Energy Physics - Phenomenology · Physics 2014-04-02 D. Gomez Dumm , S. Noguera , N. N. Scoccola , S. Scopetta

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

In this paper, we study the properties of the pion-photon transition form factor (TFF), $\gamma\gamma^{\ast} \rightarrow \pi^{0}$, by using the principle of maximum commonality (PMC) to deal with its perturbative QCD contribution up to…

High Energy Physics - Phenomenology · Physics 2023-10-26 Hua Zhou , Jiang Yan , Qing Yu , Xing-Gang Wu

We present a lattice QCD determination of the distribution amplitude (DA) of the pion and the first few Mellin moments from an analysis of the quasi-DA matrix element within the leading-twist framework. We perform our study on a HISQ…

High Energy Physics - Lattice · Physics 2022-10-21 Xiang Gao , Andrew D. Hanlon , Nikhil Karthik , Swagato Mukherjee , Peter Petreczky , Philipp Scior , Sergey Syritsyn , Yong Zhao

We reconsider QCD factorization for the leading power contribution to the $\gamma^{\ast} \gamma \to \pi^0$ form factor $F_{\gamma^{\ast} \gamma \to \pi^0} (Q^2)$ at one loop using the evanescent operator approach, and demonstrate the…

High Energy Physics - Phenomenology · Physics 2018-01-17 Yu-Ming Wang , Yue-Long Shen

The pion electromagnetic form factor is investigated by using the dispersion relation with the superconvergence condition, which was proposed to synthesize the vector meson dominance model and QCD. The absorptive part is given as an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Keiji Watanabe , Hirohisa Ishikawa , Masami Nakagawa

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