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
$-10\leq s\leq1$ GeV$^2$ without introducing the
phenomenological Blatt–Weisskopf range parameter $R_\pi$.
Citation:
N. N. Achasov, A. A. Kozhevnikov, “Pion form factor in the range $-10\leq s\leq1$ GeV$^2$”, Pis'ma v Zh. Èksper. Teoret. Fiz., 96:9 (2012), 627–631; JETP Letters, 96:9 (2012), 559–563