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arXiv · hep-ph/9408233

Electromagnetic Pion Form Factor and Neutral Pion Decay Width

Craig D. Roberts
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Abstract

The electromagnetic pion form factor, $F_π(q^2)$, is calculated for spacelike-$q^2$ in impulse approximation using a confining quark propagator, $S$, and a dressed quark-photon vertex, $Γ_μ$, obtained from realistic, nonperturbative Dyson-Schwinger equation studies. Good agreement with the available data is obtained for $F_π(q^2)$ and other pion observables, including the decay $π^0 \rightarrow γ\,γ$. This calculation suggests that soft, nonperturbative contributions dominate $F_π(q^2)$ at presently accessible~$q^2$.

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Craig D. Roberts. 1996-04-23. Electromagnetic Pion Form Factor and Neutral Pion Decay Width. https://doi.org/10.1016/0375-9474(96)00174-1

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