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Related papers: The electromagnetic pion form factor and its phase

200 papers

We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion…

High Energy Physics - Lattice · Physics 2011-09-02 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

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 simultaneous investigation of the pion electromagnetic form factor in the space- and time-like regions within a light-front model allows one to address the issue of non-valence components of the pion and photon wave functions. Our…

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

We consider finite volume effects on the electromagnetic form factor of the pion. We compute the peudoscalar-vector-pseudoscalar correlator in the $\epsilon$ expansion of chiral perturbation theory up to the next-to-leading order and find a…

High Energy Physics - Lattice · Physics 2014-12-31 Hidenori Fukaya , Takashi Suzuki

We analyze the electromagnetic pion and kaon form factor by including radiative and higher-twist effects within the framework of resummed pQCD in the space-like region. We focus on the transition from the perturbative to non-perturbative…

High Energy Physics - Phenomenology · Physics 2009-03-02 Udit Raha , Andreas Aste

We consider how to extract the pion form factors in the epsilon regime. Using the correlators with non-zero momenta and taking appropriate ratios of them, we eliminate the dominant finite volume effect from the zero-momentum pion mode. Our…

High Energy Physics - Lattice · Physics 2012-11-06 JLQCD Collaboration , H. Fukaya , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki , T. Onogi , N. Yamada

The electromagnetic form factor of the pion is calculated in a pseudoscalar field theoretical model which constituent quarks. We extract the form factor using the "+" component of the electromagnetic current in the light-cone formalism. For…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. P. B. C. de Melo , H. W. L. Naus , T. Frederico

We calculate the electromagnetic form factor of the pion in quenched lattice QCD. The non-perturbatively improved Sheikoleslami-Wohlert lattice action is used together with the consistently O(a) improved current. We calculate the pion form…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. H. Koch , E. Laermann

A new formula for the pion form factor F_pi is proposed which takes into account the pseudoscalar meson loops and the mixing among rho(770), rho(1450), and rho(1700). The expression possesses correct analytical properties and can be used in…

High Energy Physics - Phenomenology · Physics 2011-06-30 N. N. Achasov , A. A. Kozhevnikov

We comment on the results of a complete leading-twist next-to-leading order QCD analysis of the spacelike pion electromagnetic form factor at large-momentum transfer Q. For the asymptotic distribution amplitude, we have examined the…

High Energy Physics - Phenomenology · Physics 2009-08-25 B. Melic , B. Nizic , K. Passek

The factorization theorem for exclusive processes in perturbative QCD predicts the behavior of the pion electromagnetic form factor $F(t)$ at asymptotic spacelike momenta $t(=-Q^2)<0$. We address the question of the onset energy using a…

High Energy Physics - Phenomenology · Physics 2012-06-01 B. Ananthanarayan , Irinel Caprini , I. Sentitemsu Imsong

This talk presents issues pertaining to the quark structure of the pion within QCD, both from the theoretical and from the experimental point of view. We review and discuss the pion-photon transition form factor and the pion's…

High Energy Physics - Phenomenology · Physics 2008-11-07 N. G. Stefanis

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

The charge form factor of the pion is calculated in lattice QCD. The non-perturbatively improved Sheikholeslami-Wohlert action is used together with the $\mathcal{O}(a)$ improved vector current. Other choices for the current are examined.…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. Koch , E. Laermann

Recent data from high statistics experiments that have measured the modulus of the pion electromagnetic form factor from threshold to relatively high energies are used as input in a suitable mathematical framework of analytic continuation…

High Energy Physics - Phenomenology · Physics 2013-08-13 B. Ananthanarayan , I. Caprini , Diganta Das , I. Sentitemsu Imsong

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

We calculate upper and lower bounds on the modulus of the pion electro magnetic form factor on the unitarity cut below the $\omega\pi$ inelastic threshold, using as input the phase in the elastic region known via the Fermi-Watson theorem…

High Energy Physics - Phenomenology · Physics 2012-10-26 B. Ananthanarayan , I. Caprini , Diganta Das , I. Sentitemsu Imsong

We perform a nonperturbative lattice calculation of the complex phase and modulus of the pion form factor in the timelike momentum region using the finite-volume technique. We use two ensembles of 2+1-flavor overlap fermion at pion masses…

High Energy Physics - Lattice · Physics 2015-03-18 Xu Feng , Sinya Aoki , Shoji Hashimoto , Takashi Kaneko

The pion electromagnetic form factor is calculated at lower and higher momentum transfer in order to explore constituent quark models and the differences among those models. In particular, the light-front constituent quark model is utilized…

High Energy Physics - Phenomenology · Physics 2016-10-19 J. P. B. C. de Melo , Rômulo Moreira Moita , Kazuo Tsushima

The experimental data on the electromagnetic form factor of charged pions available at spacelike momenta are analyzed using the Dispersive Matrix (DM) approach, which describes the momentum dependence of hadronic form factors without…

High Energy Physics - Phenomenology · Physics 2023-10-20 S. Simula , L. Vittorio