Study of the process e+e- -->π+π- π0 in the energy region (s) from 0.98 to 1.38 GeV
Abstract
The cross section of the process e+e--->π+π- π0 was measured in the Spherical Neutral Detector experiment at the VEPP-2M collider in the energy region (s)=980-1380 MeV. The measured cross section, together with the e+e--->π+π- π0 and ωπ+π- cross sections obtained in other experiments, was analyzed in the framework of the generalized vector meson dominance model. It was found that the experimental data can be described by a sum of ω, φ mesons and two ω' and ω'' resonances contributions, with masses mω'~1490, mω''~1790 MeV and widths Γω'~1210, Γω''~560 MeV. The analysis of the π+π- invariant mass spectra in the energy region (s) from 1100 to 1380 MeV has shown that for their description one should take into account the e+e- -->ωπ0-->π+π- π0 mechanism also. The phase between the amplitudes corresponding to the e+e--->ωπ and e+e--->ρπ intermediate states was measured for the first time. The value of the phase is close to zero and depends on energy.
- Publication:
-
Physical Review D
- Pub Date:
- August 2002
- DOI:
- 10.1103/PhysRevD.66.032001
- arXiv:
- arXiv:hep-ex/0201040
- Bibcode:
- 2002PhRvD..66c2001A
- Keywords:
-
- 13.65.+i;
- 12.40.Vv;
- 13.25.Jx;
- Vector-meson dominance;
- Decays of other mesons;
- High Energy Physics - Experiment
- E-Print:
- 29 pages REVTEX and 17 figures, accepted for publication in Physical Review D