English
Related papers

Related papers: The pion form factor from first principles

200 papers

We present a lattice QCD calculation of the pion scalar form factor and associated radii with fully controlled systematics. Lattice results are computed on a large set of 17 gauge ensembles with $N_f=2+1$ Wilson Clover-improved sea quarks.…

High Energy Physics - Lattice · Physics 2025-03-27 Konstantin Ottnad , Georg von Hippel

We present a formula that allows one to calculate the pion form factor in the timelike region 2mpi <= sqrt{s} <= 4mpi in lattice QCD. The form factor quantifies the contribution of two-pion states to the vacuum polarization. It must be…

High Energy Physics - Lattice · Physics 2012-04-04 Harvey B. Meyer

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 pion form factor is computed using quenched twisted mass QCD and the GMRES-DR matrix inverter. The momentum averaging procedure of Frezzotti and Rossi is used to remove leading lattice spacing artifacts, and numerical results for the…

High Energy Physics - Lattice · Physics 2009-11-10 Abdou M. Abdel-Rehim , Randy Lewis

We present an investigation of pion structure based on ETMC $N_f=2$ and $N_f=2+1+1$ twisted mass configurations at maximal twist. We compute the first moment of the quark momentum fraction of the pion, $\langle x \rangle$ and the…

High Energy Physics - Lattice · Physics 2016-12-06 Bartosz Kostrzewa , Maximilian Oehm , Francesco Sanfilippo , Silvano Simula , Carsten Urbach

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

We present the first calculation of the electromagnetic form factor of the $\pi$ meson at physical light quark masses. We use configurations generated by the MILC collaboration including the effect of $u$, $d$, $s$ and $c$ sea quarks with…

High Energy Physics - Lattice · Physics 2016-03-23 J. Koponen , F. Bursa , C. T. H. Davies , R. J. Dowdall , G. P. Lepage

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

We present a precise calculation of the pion form factor using overlap fermions on seven ensembles of 2+1-flavor domain-wall configurations with pion masses varying from 139 to 340 MeV. Taking advantage of the fast Fourier transform and…

High Energy Physics - Phenomenology · Physics 2021-10-13 Gen Wang , Jian Liang , Terrence Draper , Keh-Fei Liu , Yi-Bo Yang

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

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 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

The electromagnetic pion form factor, $F_\pi(q^2)$, is calculated for spacelike-$q^2$ in impulse approximation using a confining quark propagator, $S$, and a dressed quark-photon vertex, $\Gamma_\mu$, obtained from realistic,…

High Energy Physics - Phenomenology · Physics 2010-03-04 Craig D. Roberts

In this work, we analyze the electromagnetic structure of the pion. We calculate its electromagnetic radius and electromagnetic form factor in low and intermediate momentum range. Such observables are determined by means of a theoretical…

High Energy Physics - Phenomenology · Physics 2015-06-11 Clayton S. Mello , José P. Cruz Filho , Edson O. da Silva , J. P. B. C. de Melo , Bruno El-Bennich , Victo S. Filho

This review contains an overview over recent results for the electromagnetic iso-vector form factor of the pion obtained in lattice QCD with dynamical fermions. Particular attention is given to the extrapolation to the physical point and an…

High Energy Physics - Lattice · Physics 2014-02-14 Bastian B. Brandt

We present lattice QCD calculations of nucleon electromagnetic form factors using pion masses $m_\pi$ = 149, 202, and 254 MeV and an action with clover-improved Wilson quarks coupled to smeared gauge fields, as used by the…

High Energy Physics - Lattice · Physics 2014-11-20 J. R. Green , J. W. Negele , A. V. Pochinsky , S. N. Syritsyn , M. Engelhardt , S. Krieg

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 study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of…

High Energy Physics - Phenomenology · Physics 2023-07-26 Jian Chai , Shan Cheng , Jun Hua

We develop a methodology that enables us to extract accurately the electromagnetic Delta form factors and their momentum dependence. We test our approach in the quenched approximation as a preparation for a study using dynamical fermions.…

High Energy Physics - Lattice · Physics 2008-11-26 Constantia Alexandrou , Tomasz Korzec , Theodoros Leontiou , John W. Negele , Antonios Tsapalis

We study the chiral behavior of the electromagnetic (EM) form factors of pion and kaon in three-flavor lattice QCD. In order to make a direct comparison of the lattice data with chiral perturbation theory (ChPT), we employ the overlap quark…

High Energy Physics - Lattice · Physics 2016-02-24 JLQCD Collaboration , S. Aoki , G. Cossu , X. Feng , S. Hashimoto , T. Kaneko , J. Noaki , T. Onogi