Hidden local symmetry and the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- at energies \sqrt{s}\leq 1 GeV

Abstract

Based on the generalized hidden local symmetry as the chiral model of pseudoscalar, vector, and axial vector mesons, the excitation curve of the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- is calculated for energies in the interval 0.65\leq \sqrt{s}\leq1 GeV. The theoretical predictions are compared to available data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances \rho(1450) and \rho(1700) is necessary for reconciling calculations with the data. It is found that at \sqrt{s}\approx1 GeV the contributions of the above resonances are much larger, by the factor of 30, than the \rho(770) one, and are amount to a considerable fraction \sim0.3-0.6 of the latter at \sqrt{s}\sim m_\rho.

Comments: 9 pages, 3 figures, 2 tables; accepted for publication in European Phys. Journal A