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Related papers: The Pion Form Factor. Where Does It Come From?

200 papers

In this paper, by employing the $k_{T}$ factorization theorem, we calculate firstly the next-to-leading-order (NLO) twist-3 contributions to the pion electromagnetic form factors in the $\pi\gamma^* \to \pi$ process. From the analytical and…

High Energy Physics - Phenomenology · Physics 2014-03-26 Shan Cheng , Ying-Ying Fan , Zhen-Jun Xiao

In this article, we calculate the scalar form-factor of the proton in the framework of the light-cone QCD sum rules approach with the three valence quark light-cone distribution amplitudes up to twist-6, and observe the scalar form-factor…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zhi-Gang Wang , Shao-Long Wan , Wei-Min Yang

We scrutinize recent findings on the charged-pion elastic form factor and the form factors entering in neutral-meson-to-photons transition amplitudes within the framework of QCD sum rules.

High Energy Physics - Phenomenology · Physics 2015-06-05 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

We present a calculation of the electromagnetic form factor of the pion in $N_f=2+1$ flavor lattice QCD. Calculations are made on the PACS-CS gauge field configurations generated using Iwasaki gauge action and Wilson-clover quark action on…

High Energy Physics - Lattice · Physics 2011-05-09 Oanh Hoang Nguyen , Ken-Ichi Ishikawa , Akira Ukawa , Naoya Ukita

The two gravitational form factors of the pion, $A^{\pi}(t)$ and $D^{\pi}(t)$, are computed as functions of the momentum transfer squared $t$ in the kinematic region $0\leq -t< 2~\text{GeV}^2$ on a lattice QCD ensemble with quark masses…

High Energy Physics - Lattice · Physics 2023-12-12 Daniel C. Hackett , Patrick R. Oare , Dimitra A. Pefkou , Phiala E. Shanahan

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

We accomplish the complete two-loop computation of the leading-twist contribution to the photon-pion transition form factor $\gamma \, \gamma^{\ast} \to \pi^0$ by applying the hard-collinear factorization theorem together with modern…

High Energy Physics - Phenomenology · Physics 2022-02-18 Jing Gao , Tobias Huber , Yao Ji , Yu-Ming Wang

Using our present knowledge on effective hadronic theories, short-distance QCD information, the $1/N_C$ expansion, analyticity and unitarity, we derive an expression for the pion form factor, in terms of $m_\pi, m_K, M_\rho$ and $f_\pi$.…

High Energy Physics - Phenomenology · Physics 2011-05-05 F. Guerrero , A. Pich

We study the electromagnetic pion form factor and the VV - AA two point function for momenta -(600 MeV)^2 < q^2 < (600 MeV)^2 and we note the similarity between vector meson dominance and two versions of the free constituent quark model.…

High Energy Physics - Phenomenology · Physics 2009-10-22 B. Holdom

We calculate the scalar form factor of the pion using two dynamical flavors of non-perturbatively $\mathcal{O}(a)$-improved Wilson fermions, including both the connected and the disconnected contribution to the relevant correlation…

High Energy Physics - Lattice · Physics 2014-05-14 Vera Gülpers , Georg von Hippel , Hartmut Wittig

The transition form factor, decay width and charge form factor of pion are calculated within the model of induced nonlocal quark currents based on the assumption that the nonperturbative QCD vacuum can be characterized by a homogeneous…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ja. V. Burdanov , G. V. Efimov , S. N. Nedelko

A new picture is given of generalized parton distributions probed in experiments in which the probe scale $Q^{2}$ and the momentum transfer $\DD^{2}$ are well separated. Application of this picture to the $Q^{2}$ dependence of the form…

High Energy Physics - Phenomenology · Physics 2015-06-25 John P. Ralston , Roman V. Buniy , Pankaj Jain

The electromagnetic form factors of pion and nucleon are considered within the framework of the Quark-Gluon Strings Model, where the dependence of the form factors on $q^2$ is determined by the intercept of a dominant Regge trajectory and…

High Energy Physics - Phenomenology · Physics 2009-08-25 A. B. Kaidalov , L. A. Kondratyuk , D. V. Tchekin

We present results of a calculation of the electromagnetic pion form factor within the framework of QCD Sum Rules with nonlocal condensates, using a perturbative spectral density which includes $O(\alpha_s)$ contributions.

High Energy Physics - Phenomenology · Physics 2014-11-18 Alexander P. Bakulev , A. V. Pimikov , N. G. Stefanis

The meson-photon transition form factors $\gamma\gamma^*\to P$ ($P$ stands for $\pi$, $\eta$ and $\eta'$) provide strong constraints on the distribution amplitudes of the pseudoscalar mesons. In this paper, these transition form factors are…

High Energy Physics - Phenomenology · Physics 2011-10-11 Xing-Gang Wu , Tao Huang

We propose to introduce the intrinsic transversal momentum distribution functions (iTMDs), in conjunction with the light-cone distribution amplitudes (LCDAs), to elucidate the probability amplitude of encountering a meson state wherein the…

High Energy Physics - Phenomenology · Physics 2025-03-25 Jian Chai , Shan Cheng

We report on our computation of the pion transition form factor ${\cal F}_{P\rightarrow \gamma^*\gamma^*}$ from twisted mass lattice QCD in order to determine the numerically dominant light pseudoscalar pole contribution in the hadronic…

We develop a relativistic quark model for pion structure, which incorporates the non-trivial structure of the vacuum of Quantum Chromodynamics as modelled by instantons. Pions are boundstates of quarks and the strong quark-pion vertex is…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. V. Anikin , A. E. Dorokhov , A. E. Maximov , L. Tomio , V. Vento

We present the first calculation of the momentum-transfer dependence of the pion gravitational form factors (GFFs) within a top-down holographic QCD framework. These form factors encode essential information about the internal stress…

High Energy Physics - Phenomenology · Physics 2025-04-03 Mitsuru Tanaka , Daisuke Fujii , Akihiro Iwanaka

We revisit $F_\pi(Q^2)$ and $F_{P\gamma}(Q^2)$, $P=\pi,\eta,\eta'$, making use of the local-duality (LD) version of QCD sum rules. We give arguments, that the LD sum rule provides reliable predictions for these form factors at $Q^2 \ge 5-6$…

High Energy Physics - Phenomenology · Physics 2013-03-15 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov