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Related papers: Pion form factor in large $N_c$ QCD

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The electromagnetic form factors of the proton are obtained using a particular realization of QCD in the large $N_c$ limit (${QCD}_{\infty}$), which sums up the infinite number of zero-width resonances to yield an Euler's Beta function…

High Energy Physics - Phenomenology · Physics 2010-02-03 C. A. Dominguez , T. Thapedi

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward…

High Energy Physics - Phenomenology · Physics 2024-10-24 Pablo Sanchez-Puertas , Enrique Ruiz Arriola

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 results of a calculation of the electromagnetic pion form factor within a framework of QCD Sum Rules with nonlocal condensates and using a perturbative spectral density which includes \mathcal{O}(\alpha_s) contributions.

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

The electromagnetic form factor of the pion is calculated in the "point-form" of relativistic quantum mechanics using simple, phenomenological wave functions. It is found that the squared charge radius of the pion is predicted one order of…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. Amghar , B. Desplanques , L. Theussl

We present detailed numerical results for the pion space-like electromagnetic form factor obtained within a recently proposed model of the pion electromagnetic current in a confining light-front QCD-inspired model. The model incorporates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo , T. Frederico , E. Pace , G. Salme

The pion form factor at very large $Q^2$ is obtained by using a new pion wave function. It shows that when $Q^2>>(1.8GeV)^2$ the pion form factor reaches the asymptotic limit ${\alpha_s(Q^2)\over Q^2}$

High Energy Physics - Phenomenology · Physics 2007-05-23 Bing An Li

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 present a construction of the pion electromagnetic form factor where the transition from large-Nc Regge vector meson dominance models with infinitely many resonances to perturbative QCD is built in explicitly. The construction is based…

High Energy Physics - Phenomenology · Physics 2008-11-26 Enrique Ruiz Arriola , Wojciech Broniowski

In this talk, results are presented of determinations of electromagnetic form factors of hadrons (pion, proton, and $\Delta(1236)$) in the framework of Dual-Large $N_c$ QCD (Dual-$QCD_\infty$). This framework improves considerably…

High Energy Physics - Phenomenology · Physics 2015-05-18 C. A. Dominguez

The pion electromagnetic form factor is calculated in the space- and time-like regions from -10 $(GeV/c)^2$ up to 10 $(GeV/c)^2$, within a front-form model. The dressed photon vertex where a photon decays in a quark-antiquark pair is…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo , T. Frederico , E. Pace , G. Salme`

The pion electromagnetic form factor and two-pion production in electron-positron collisions are simultaneously fitted by a vector dominance model evolving to perturbative QCD at large momentum transfer. This model was previously successful…

High Energy Physics - Phenomenology · Physics 2016-09-14 Earle L. Lomon , Simone Pacetti

We analyze the pi -> gamma* gamma* amplitude in the framework of radial Regge models in the large-Nc limit. With the assumption of similarity of the asymptotic Regge rho and omega meson spectra we find that the pion distribution amplitude…

High Energy Physics - Phenomenology · Physics 2008-11-26 Enrique Ruiz Arriola , Wojciech Broniowski

We extend recently developed methods used for determining the electromagnetic charge radius and $a_\mu^{\pi\pi}$ to obtain a determination of the electromagnetic form factor of the pion, $F_\pi^V(t)$, in several significant kinematical…

High Energy Physics - Phenomenology · Physics 2019-01-02 B. Ananthanarayan , Irinel Caprini , Diganta Das

We extend a recent analysis of the pion electromagnetic form factor constrained by the conformal symmetry to explore the time-like region. We show explicitly that the time-like form factor obtained by the analytic continuation of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ho-Meoyng Choi , Chueng-Ryong Ji

The problem of determining the pion electromagnetic formfactor $F(q^2)$ in the space-like region from the value of its modulus in the time-like region is solved by the formfactor analyticity. If $F(q^2)$has no zeroes in the complex plane…

High Energy Physics - Phenomenology · Physics 2009-10-31 B. V. Geshkenbein

We present the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits the pion. These deviations…

High Energy Physics - Lattice · Physics 2017-10-23 Jonna Koponen , Francis Bursa , Christine T. H. Davies , Rachel J. Dowdall , G. Peter Lepage

The electromagnetic form factor of the pion is calculated within the use of functional formalism. We develop integral representation for the minimal set of Standard Model Green's functions and derive the dispersion relation for the form…

High Energy Physics - Phenomenology · Physics 2022-09-30 Vladimir Sauli

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…

NNLO QCD corrections for the pion electromagnetic form factor at large momentum transfer have been recently performed in [Phys. Rev. Lett. 132, 201901 (2024); Phys. Rev. Lett. 134, 221901 (2025)], revealing that the NLO and NNLO…

High Energy Physics - Phenomenology · Physics 2025-12-29 Sheng-Quan Wang , Zuo-Fen Liao , Jian-Ming Shen , Hua Zhou , Jia-Wei Zhang , Jiang Yan , Xing-Gang Wu , Leonardo Di Giustino
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