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Electromagnetic form factor of the pion in the space- and time-like regions within the front-form dynamics

J. P. B. C. de Melo·T. Frederico·E. Pace·G. Salme`
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Abstract

The pion electromagnetic form factor is calculated in the space- and time-like regions from -10 $(GeV/c)^2$ up to 10 $(GeV/c)^2$, within a front-form model. The dressed photon vertex where a photon decays in a quark-antiquark pair is depicted generalizing the vector meson dominance ansatz, by means of the vector meson vertex functions. An important feature of our model is the description of the on-mass-shell vertex functions in the valence sector, for the pion and the vector mesons, through the front-form wave functions obtained within a realistic quark model. The theoretical results show an excellent agreement with the data in the space-like region, while in the time-like region the description is quite encouraging.

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J. P. B. C. de Melo, T. Frederico, E. Pace, G. Salme`. 2003-11-28. Electromagnetic form factor of the pion in the space- and time-like regions within the front-form dynamics. https://doi.org/10.1016/j.physletb.2003.11.072

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