| Summary: | We study the process e[superscript +]e[superscript −] → ψ(2S)π[superscript +]π[superscript −] with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies at and near the Υ(nS) (n = 2,3,4) resonances and correspond to an integrated luminosity of 520 fb[superscript −1]. We investigate the ψ(2S)π[superscript +]π[superscript −] mass distribution from 3.95 to 5.95 GeV/c[superscript 2], and measure the center-of-mass energy dependence of the associated e[superscript +]e[superscript −] → ψ(2S)π[superscript +]π[superscript −] cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the ψ(2S)π[superscript +]π[superscript −] mass distribution corresponding to the decay mode ψ(2S) → J/ψπ[superscript +]π[superscript −] yields a mass value of 4340 ± 16 (stat) ± 9 (syst) MeV/c[superscript 2] and a width of 94 ± 32 (stat) ± 13 (syst) MeV for the first resonance, and for the second a mass value of 4669 ± 21 (stat) ± 3 (syst) MeV/c[superscript 2] and a width of 104 ± 48 (stat) ± 10 (syst) MeV. In addition, we show the π[superscript +]π[superscript −] mass distributions for these resonant regions.
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