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arXiv · 1209.5524

Pion form factor in the range -10 GeV^2 < s < 1 GeV^2

N. N. Achasov·A. A. Kozhevnikov
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Abstract

Based on the field-theory-inspired approach, a new expression for the pion form factor F_pi is proposed. It takes into account the pseudoscalar meson loops $\pi^+\pi^-$ and $K\bar K$ and the mixing of $\rho(770)$ with heavier $\rho(1450)$ and $\rho(1700)$ resonances. The expression possesses correct analytical properties and describes the data in the wide range of the energy squared $-10{GeV}^2\leq s\leq1$ GeV$^2$ without introducing the phenomenological Blatt -- Weisskopf range parameter $R_\pi$.

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N. N. Achasov, A. A. Kozhevnikov. 2012-09-25. Pion form factor in the range -10 GeV^2 < s < 1 GeV^2. https://doi.org/10.1134/s0021364012210023

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