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Space-like and time-like pion electromagnetic form factor and Fock state components within the Light-Front dynamics

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

The simultaneous investigation of the pion electromagnetic form factor in the space- and time-like regions within a light-front model allows one to address the issue of non-valence components of the pion and photon wave functions. Our relativistic approach is based on a microscopic vector meson dominance (VMD) model for the dressed vertex where a photon decays in a quark-antiquark pair, and on a simple parametrization for the emission or absorption of a pion by a quark. The results show an excellent agreement in the space like region up to -10 $(GeV/c)^2$, while in time-like region the model produces reasonable results up to 10 $(GeV/c)^2$.

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J. P. B. C. de Melo, T. Frederico, E. Pace, G. Salme. 2005-07-29. Space-like and time-like pion electromagnetic form factor and Fock state components within the Light-Front dynamics. https://doi.org/10.1103/physrevd.73.074013

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