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Related papers: The Pion Form Factor at Large Momentum Transfer

200 papers

We study the pion form factor in a broad range of spacelike momentum transfers within the local-duality version of QCD sum rules. We make use of the recently calculated two-loop double spectral density of the $<AVA>$ correlator including…

High Energy Physics - Phenomenology · Physics 2008-11-26 Victor Braguta , Wolfgang Lucha , Dmitri Melikhov

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 use recent data on K^+ -> pi^+ e^+ e^-, together with known values for the pion form factor, to derive experimental values for the kaon electromagnetic form factor for 0 < q^2 < 0.125 (GeV/c)^2. The results are then compared with the…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Lowe , M. D. Scadron

New, accurate measurements of the pion and kaon electromagnetic form factors are expected in the near future from experiments at electron-positron colliders,using the radiative return method. We construct a model for the timelike pion…

High Energy Physics - Phenomenology · Physics 2015-06-25 Christine Bruch , Alexander Khodjamirian , Johann H. Kuhn

We consider the fidelity of the vector meson dominance (VMD) assumption as an instrument for relating the electromagnetic vector-meson production reaction $e + p \to e^\prime + V + p$ to the purely hadronic process $V + p \to V+p$. Analyses…

High Energy Physics - Phenomenology · Physics 2023-10-25 Yin-Zhen Xu , Si-Yang Chen , Zhao-Qian Yao , Daniele Binosi , Zhu-Fang Cui , Craig D. Roberts

We have reexamined the elastic pion form factor over a broad range of momentum transfers with the mass evolution from current quark to constituent quark being taken into account. We have also studied the effect of Sudakov form factors, of…

High Energy Physics - Phenomenology · Physics 2016-09-01 Leonard S. Kisslinger , Siwen Wang

We study the pion electromagnetic and $\gamma^* + \pi^0 \to \gamma$ transition form factors at intermediate momentum transfer. We calculate soft, nonperturbative corrections to the leading perturbative amplitudes which arise from the $q\bar…

High Energy Physics - Phenomenology · Physics 2010-03-04 A. Szczepaniak , A. G. Williams

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

We have started a program to compute the electromagnetic form factors of mesons. We discuss the techniques used to compute the pion form factor and present preliminary results computed with domain wall valence fermions on MILC asqtad…

High Energy Physics - Lattice · Physics 2014-11-17 LHPC Collaboration , Frederic D. R. Bonnet , Robert G. Edwards , George T. Fleming , Randy Lewis , David G. Richards

The first three coefficients of the Taylor's series expansion of the vector pion form factor as a function of the momentum transfer are evaluated using experimental data on the pion form factor and the P-wave pi pi phase shifts. The real…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tran N. Truong

The suggestion of momentum dependence in the amplitude for rho-omega mixing has generated concern over related implications for vector meson dominance and the photon-rho coupling. We discuss two established representations of vector meson…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. B. O'Connell , B. C. Pearce , A. W. Thomas , A. G. Williams

By means of QCD sum rules in local-duality limit, we analyze the behaviour of the form factors for the transitions of a real and a virtual photon to some pseudoscalar meson as functions of the involved momentum transfer. Except for the…

High Energy Physics - Phenomenology · Physics 2012-12-27 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

We discuss the photon to meson transition form factor for virtual photons, which can be measured in e+ e- collisions. We demonstrate that this form factor is independent of the shape of the meson distribution amplitude over a wide…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Diehl , P. Kroll , C. Vogt

Confronted with some surprising claims about experimentally measured or theoretically expected dependencies on the involved momentum transfer of various form factors of pseudoscalar mesons, we reassess the present status of these quantities…

High Energy Physics - Phenomenology · Physics 2012-11-01 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

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 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

We report on a program to compute the electromagnetic form factors of mesons. We discuss the techniques used to compute the pion form factor and present results computed with domain wall valence fermions on MILC asqtad lattices, as well as…

High Energy Physics - Lattice · Physics 2014-11-17 LHP Collaboration , Frederic D. R. Bonnet , Robert G. Edwards , George T. Fleming , Randy Lewis , David G. Richards

In a study of the elastic pion form factor for large momentum transfers based on a modified perturbative QCD (PQCD) approach we have included helicity components that are customarily neglected. Along with the inclusion of transverse…

High Energy Physics - Phenomenology · Physics 2009-10-28 Siwen Wang , Leonard S. Kisslinger

Separated longitudinal and transverse structure functions for the reaction 1H(e,eprime pi+)n were measured in the momentum transfer region Q2=0.6-1.6 (GeV/c)**2 at a value of the invariant mass W=1.95 GeV. New values for the pion charge…

Nuclear Experiment · Physics 2009-04-15 J. Volmer

We consider the electromagnetic and transition pion form factors. Using dispersion relations we simultaneously describe both the hadronic, time-like region and the asymptotic region of large energy-momentum transfer. For the latter we…

High Energy Physics - Phenomenology · Physics 2011-06-28 Mikhail Gorchtein , Peng Guo , Adam P. Szczepaniak