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Related papers: Pion form factor in the Kroll-Lee-Zumino model

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We present an investigation of the pion's electromagnetic form factor F_{\pi}(Q^2) in the spacelike region utilizing two new ingredients: (i) a double-humped, endpoint-suppressed pion distribution amplitude derived before via QCD sum rules…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. P. Bakulev , K. Passek-Kumerički , W. Schroers , N. G. Stefanis

Motivated by recent measurements at J-Lab, the pion electromagnetic form-factor is investigated with quenched domain wall fermions and a renormalization group improved gauge action called DBW2. We see that quark mass dependence of the…

High Energy Physics - Lattice · Physics 2009-11-10 Y. Nemoto , RBC Collaboration

We use a version of the instant-form relativistic quantum mechanics of composite systems to obtain the gravitational form factors of the pion in a common approach to its electroweak and gravitational properties. In the preceding work…

High Energy Physics - Phenomenology · Physics 2022-09-16 A. F. Krutov , V. E. Troitsky

We evaluate the vector and scalar form factor of the pion in the presence of virtual photons at next-to-leading order in two-flavor chiral perturbation theory. We also consider the scalar and tensor pion form factors of the energy-momentum…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bastian Kubis , Ulf-G. Meißner

We report on the fully analytic calculation of the leading-power contribution to the photon-pion transition form factor $\gamma \, \gamma^{\ast} \to \pi^0$ at two loops in QCD. The applied techniques are based on hard-collinear…

High Energy Physics - Phenomenology · Physics 2021-10-29 Jing Gao , Tobias Huber , Yao Ji , Yu-Ming Wang

The form factors of the semileptonic $B\to \pi\pi\ell\bar\nu$ decay are calculated from QCD light-cone sum rules with the distribution amplitudes of dipion states. This method is valid in the kinematical region, where the hadronic dipion…

High Energy Physics - Phenomenology · Physics 2016-04-20 Christian Hambrock , Alexander Khodjamirian

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

We provide a novel approach to calculate the gravitational form factor of pion under the ladder approximation of the Bethe-Salpeter equation, with contact interactions. Central to this approach is a symmetry-preserving treatment of the…

High Energy Physics - Phenomenology · Physics 2023-03-01 Zanbin Xing , Minghui Ding , Lei Chang

The transition pion-photon form factor is studied within the framework of Light-Cone QCD Sum Rules. The spectral density for the next-to-leading order corrections is calculated for any Gegenbauer harmonic. At the level of the…

High Energy Physics - Phenomenology · Physics 2011-05-13 S. V. Mikhailov , N. G. Stefanis

We present a systematic lattice calculation of the vector and axial vector form factors $V$ and $A_i~(i=0,1,2)$ for the $D_s \to \phi \ell \nu_\ell$ semileptonic decay using (2+1)-flavor Wilson-clover fermion configurations generated by the…

High Energy Physics - Lattice · Physics 2026-01-27 Gaofeng Fan , Yu Meng , Chuan Liu , Zhaofeng Liu , Tinghong Shen , Ting-Xiao Wang , Ke-Long Zhang , Lei Zhang

We report on a calculation of form factors for the semileptonic decay of $B$ meson to pion on $2+1$-flavour lattices with lattice spacings from 0.080 fm down to 0.044 fm. Using the M\"obius domain wall fermion action for both sea and…

High Energy Physics - Lattice · Physics 2020-01-09 Brian Colquhoun , Shoji Hashimoto , Takashi Kaneko , Jonna Koponen

We calculate the nucleon form factors G_A and G_P of the isovector axial-vector current and the pion-nucleon form factor G_piN in manifestly Lorentz-invariant baryon chiral perturbation theory up to and including order O(p^4). In addition…

Nuclear Theory · Physics 2008-11-26 M. R. Schindler , T. Fuchs , J. Gegelia , S. Scherer

We analyse the pion electromagnetic, charged-current, and $\pi\gamma$ transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$ GeV$^2$, using a dispersion approach. We discuss in detail the propagator matrix of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Melikhov , O. Nachtmann , V. Nikonov , T. Paulus

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

Employing the Bethe-Salpeter formalism, we present a computation of the space-like baryonic form factor for the pion and kaon. In the exact isospin-symmetric limit this observable is forbidden by $G$-parity, so that any nonzero signal…

High Energy Physics - Phenomenology · Physics 2026-05-26 A. S. Miramontes , J. M. Morgado , J. Papavassiliou

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 valence generalized parton distribution functions (GPDs) of pion at zero skewness applying a theoretical approach in which the valence GPDs are related to valence quark distribution functions, directly. To this end, we use…

High Energy Physics - Phenomenology · Physics 2025-02-26 H. Nematollahi , K. Azizi

We calculate the vector and scalar form factors of the pion to two loops in Chiral Perturbation Theory. We estimate the unknown O(p^6) constants using resonance exchange. We make a careful comparison to the available data and determine two…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Bijnens , G. Colangelo , P. Talavera

The impulse-approximation expression used hitherto to define the pion's valence-quark distribution function is flawed because it omits contributions from the gluons which bind quarks into the pion. A corrected leading-order expression…

We calculate the time-like pion-photon transition form factor and the pion electromagnetic form factor up to next-to-leading order (NLO) of the strong coupling constant in the leading-twist $k_T$ factorization formalism. It is found that…

High Energy Physics - Phenomenology · Physics 2013-01-15 Hao-Chung Hu , Hsiang-nan Li