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arXiv · 0803.2972

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

The cross section of reaction e^+e^-\toπ^+π^-π^+π^- is calculated for energies 0.65\leq \sqrt{s}\leq1 GeV in the framework of the generalized hidden local symmetry model. The calculations are compared with the 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 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. Reaction e^+e^-\toπ^+π^-π^+π^- at energies \sqrt{s}\leq 1 GeV. https://doi.org/10.1134/s0021364008130018

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