Rho-Omega Mixing and the Pion Form Factor in the Time-like Region

Abstract

We determine the magnitude, phase, and $s$-dependence of $ρ$-$ω$ ``mixing'' in the pion form factor in the time-like region through fits to $e^+e^- \ra π^+ π^-$ data. The associated systematic errors in these quantities, arising from the functional form used to fit the $ρ$ resonance, are small. The systematic errors in the $ρ$ mass and width, however, are larger than previously estimated.