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Related papers: Pion electromagnetic form factor in the Covariant …

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The electromagnetic form factor of the pion in the space-like region, and at finite temperature, $F_{\pi}(Q^{2},T)$, is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. A. Dominguez , M. Loewe , J. S. Rozowsky

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

We introduce a covariant approach in Minkowski space for the description of quarks and mesons that exhibits both chiral-symmetry breaking and confinement. In a simple model for the interquark interaction the quark mass function is obtained…

High Energy Physics - Phenomenology · Physics 2016-07-19 Elmar P. Biernat , M. T. Peña , Franz Gross , Alfred Stadler , Emílio Ribeiro

The charge form factor of the pion is calculated for momentum transfer range of Jefferson Lab experiments. The approach is based on the instant form of the relativistic Hamiltonian dynamics. It is shown that the form-factor dependence on…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. F. Krutov , V. E. Troitsky

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 behaviour of the pion transition form factor for the process $\gamma^\star\gamma \to \pi^0$ and $\gamma^\star\gamma^\star\to \pi^0$ at space-like values of photon momenta is estimated within the nonlocal covariant quark-meson model. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. E. Dorokhov

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 compute the pion electromagnetic form factor in a hybrid calculation with domain wall valence quarks and improved staggered (asqtad) sea quarks. This method can easily be extended to rho-to-gamma-pi transition form factors.

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

We present a calculation of the electromagnetic form factor of the pion in $N_f=2+1$ flavor lattice QCD. Calculations are made on the PACS-CS gauge field configurations generated using Iwasaki gauge action and Wilson-clover quark action on…

High Energy Physics - Lattice · Physics 2011-05-09 Oanh Hoang Nguyen , Ken-Ichi Ishikawa , Akira Ukawa , Naoya Ukita

The pion form factor calculation in the ``point-form'' of relativistic quantum mechanics is re-considered. Particular attention is given to the relation between the momentum of the system and the momentum transfer as well as to the quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Desplanques , A. Amghar , L. Theussl

We consider a model with $\rho\pi\pi$, $\rho KK$, and gauge-invariant $\rho\gamma$ couplings and obtain the pion form factor $F_\pi$ at timelike momentum transfers by resummation of pion and kaon loops. We use a dispersion representation…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Melikhov , O. Nachtmann , T. Paulus

We compute the electromagnetic charged kaon form factor in the time-like region by employing a Poincar\'e covariant formalism of the Bethe-Salpeter equation to study quark-antiquark bound states in conjunction with the Schwinger-Dyson…

High Energy Physics - Phenomenology · Physics 2023-02-01 A. S. Miramontes , Adnan Bashir

An exploratory study of the time-like pion electromagnetic form factor in a Poincar\'e-covariant bound state formalism in the isospin symmetric limit is presented. Starting from a quark interaction kernel representing gluon-intermediated…

High Energy Physics - Phenomenology · Physics 2021-06-16 Ángel S. Miramontes López , Hèlios Sanchis-Alepuz , Reinhard Alkofer

We calculate the transition form factor of the neutral pion where one photon is virtual and another photon is real in the model where the light constituent quark mass and the quark-pion vertex are taken to be momentum independent. Radiative…

High Energy Physics - Phenomenology · Physics 2013-08-09 A. E. Dorokhov , E. A. Kuraev

New precise experimental information on $\sigma_{tot}(e^+e^- \to \pi^+ \pi^-)$ is transferred into the space-like region, by taking advantage of the analyticity. As a result a rigorous pion electromagnetic form factor behavior is obtained.…

High Energy Physics - Phenomenology · Physics 2011-02-25 M. Belicka , S. Dubnicka , A. Z. Dubnickova , A. Liptaj

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 role of Poincar\'e covariant space-time translations is investigated in the case of a relativistic quantum mechanics approach to the pion charge form factor. It is shown that the related constraints are generally inconsistent with the…

Nuclear Theory · Physics 2015-05-18 Bertrand Desplanques , Yu Bing Dong

A novel method is employed to compute the pion electromagnetic form factor, F_\pi(Q^2), on the entire domain of spacelike momentum transfer using the Dyson-Schwinger equation (DSE) framework in quantum chromodynamics (QCD). The DSE…

Nuclear Theory · Physics 2015-06-16 L. Chang , I. C. Cloet , C. D. Roberts , S. M. Schmidt , P. C. Tandy

We present a lattice calculation of the electromagnetic form factor of the pion obtained using the tree-level Symanzik improved gauge action with two flavors of dynamical twisted Wilson quarks. The simulated pion masses range approximately…

High Energy Physics - Lattice · Physics 2009-11-06 R. Frezzotti , V. Lubicz , S. Simula

The pion electromagnetic form factor has been calculated for the first time from the solutions of the Bethe-Salpeter equation, obtained directly in Minkowski space by using the Nakanishi integral representation of the Bethe-Salpeter…

High Energy Physics - Phenomenology · Physics 2021-08-18 Emanuel Ydrefors , Wayne de Paula , Jorge H Alvarenga Nogueira , Tobias Frederico , Giovanni Salmé