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Related papers: Pion form factor at very large $Q^2$

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We compute the electromagnetic form factor of the pion using non-perturbatively O(a) improved Wilson fermions. The calculations are done for a wide range of pion masses and lattice spacings. We check for finite size effects by repeating…

We present the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits the pion. These deviations…

High Energy Physics - Lattice · Physics 2017-10-23 Jonna Koponen , Francis Bursa , Christine T. H. Davies , Rachel J. Dowdall , G. Peter Lepage

Motivated by the emerging possibilities to study threshold pion electroproduction at large momentum transfers at Jefferson Laboratory following the 12 GeV upgrade, we provide a short theory summary and an estimate of the nucleon axial form…

High Energy Physics - Phenomenology · Physics 2016-08-10 I. V. Anikin , V. M. Braun , N. Offen

We employ a dispersion relation that allows to recover the phase of the electromagnetic form factor of the pion from its absolute value above threshold. Compared to alternative approaches building on the phase, this approach builds on…

High Energy Physics - Phenomenology · Physics 2024-07-29 Enrique Ruiz Arriola , Pablo Sanchez-Puertas

We develop a formalism to calculate form factor and charge density distribution of pion in the chiral limit using the holographic dual model of QCD with hard-wall cutoff. We introduce two conjugate pion wave functions and present analytic…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. R. Grigoryan , A. V. Radyushkin

We discuss the pion form factor calculation in QCD.We shortly consider the main points of the nonlocal condensate QCD sum rule approach and show its results for the pion form factor, $F_\pi(Q^2)$. These results are compared with predictions…

High Energy Physics - Phenomenology · Physics 2015-05-20 Alexander P. Bakulev

We extend our relativistic theory of gravitational structure of composite hadrons to obtain the pion gravitational form factors at large momentum transfers. The approach was used in the case of intermediate region of the variable in our…

High Energy Physics - Phenomenology · Physics 2023-12-05 A. F. Krutov , V. E. Troitsky

We present preliminary results from the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits…

High Energy Physics - Lattice · Physics 2013-11-15 Jonna Koponen , Francis Bursa , Christine Davies , Gordon Donald , Rachel Dowdall

The pion electromagnetic form factor is calculated within the QCD light-cone sum rule method and using a renormalon model for the higher twist distribution amplitudes (DAs). The theoretical predictions are compared with the experimental…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. S. Agaev

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Anisovich , D. Melikhov , V. Nikonov

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

The pion electromagnetic form factor F_{\pi}(Q^{2}) is calculated at the leading order of pQCD using the running coupling constant (\alpha_{S}(Q^{2}(1-x)(1-y))) approach. The resummed expression for F_{\pi}(Q^{2}) is found. It is shown that…

High Energy Physics - Phenomenology · Physics 2008-02-03 Shahin S. Agaev

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

We present our calculations of the electromagnetic form factor of pions. We explore the properties of pion form factor at momentum transfer larger than previous studies by including more combinations of source and sink momenta and using…

High Energy Physics - Lattice · Physics 2010-12-13 Pai-hsien Jennifer Hsu , George T. Fleming

We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…

We present an analysis of QCD sum rules for pion form factor in next-to-leading order of perturbation theory for the case of axial-vector pion currents. The theoretical predictions for Q^2-dependence of pion form factor are in good…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. V. Braguta , A. I. Onishchenko

We study the pion form factor F^{\pi \gamma\gamma^*}(Q^2) in the light-cone sum rule approach, accounting for radiative corrections and higher twist effects. Comparing the results to the CLEO experimental data on F^{\pi…

High Energy Physics - Phenomenology · Physics 2016-09-06 Alexander Schmedding , Oleg Yakovlev

We use dispersive techniques to address the behavior of the pion form factor as $Q^2 \to \infty$ and $Q^2 \to 0$. We perform the matching with the constraints of perturbative QCD and chiral perturbation theory in the high energy and low…

High Energy Physics - Phenomenology · Physics 2011-07-19 John F. Donoghue , Euy Soo Na

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

We study a model-independent parameterization of the vector pion form factor that arises from the constraints of analyticity and unitarity. Our description should be suitable up to s^(1/2) ~ 1.2 GeV and allows a model-independent…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Pich , J. Portoles