ISSN - 10637761, EISSN - 10906509, Journal of Experimental and Theoretical Physics, 2009, vol. 109, p. 379-392
Study of process e + e - → π+π -π0π0 at energies √s < 1 GeV with the spherical neutral detector
The cross section for the process e + e - → π+π-π0π0 has been measured in an experiment with a spherical neutral detector, with the cross section at energies √s < 920 MeV having been measured for the first time. The model of vector dominance describes well the data obtained if the ρ, ρ′, and ρ″ resonances are taken into account. The probability of the decay ρ → π+π -π0π0 is B(ρ → π+π-π0π0) = (1.60 ± 0.74 ± 0.18) × 10-5. The upper limit for the decay ω → π+π -π0π0 has been improved by two orders of magnitude compared to previous measurements and is B(ω → π+π-π0π0) < 2 × 10-4 at a 90% confidence level. © 2009 Pleiades Publishing, Ltd.