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arXiv · 0809.3883

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

N. N. Achasov·A. A. Kozhevnikov
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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^-\toπ^+π^-π^+π^- 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 ρ(1450) and ρ(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 ρ(770) one, and are amount to a considerable fraction \sim0.3-0.6 of the latter at \sqrt{s}\sim m_ρ.

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N. N. Achasov, A. A. Kozhevnikov. 2008-09-23. Hidden local symmetry and the reaction e^+e^-\toπ^+π^-π^+π^- at energies \sqrt{s}\leq 1 GeV. https://doi.org/10.1140/epja/i2008-10654-x

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