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

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 $-10{GeV}^2\le s\le 1$ GeV${}^2$ without introducing the phenomenological Blatt -- Weisskopf range parameter $R_{\pi }$.

Comments: 5 pages, 6 figures, 1 table. Typo in Eq. (2) is fixed. arXiv admin note: substantial text overlap with arXiv:1104.4225