9 research outputs found
Measurement of omega meson parameters in pi^+pi^-pi^0 decay mode with CMD-2
About 11 200 e^+e^- -> omega -> pi^+pi^-pi^0 events selected in the center of
mass energy range from 760 to 810 MeV were used for the measurement of the
\omega meson parameters. The following results have been obtained: sigma
_{0}=(1457 \pm 23 \pm 19)nb, m_{\omega}=(782.71 \pm 0.07 \pm 0.04) MeV/c^{2},
\Gamma_{\omega}=(8.68 \pm 0.23 \pm 0.10) MeV,
\Gamma_{e^+e^-}\cdot Br (\omega -> pi^+pi^-pi^0)=
(0.528 \pm 0.012 \pm 0.007) \cdot 10^{-3} MeV.Comment: 8 pages, 4 figure
Observation of the conversion decay at CMD-2
Using 15.1^{-1} of data collected by CMD-2 in the -meson energy range,
the branching ratio of the conversion decay has been
measured for the first time: B(\phi\to\pi^0e^+e^-) = (1.22 \pm 0.34 \pm 0.21)
\cdot 10 ^{-5}.Comment: 13 pages, 6 PostScript figures, uses refmerge.sty. To be published in
Phys. Lett.
Study of the Process e+ e- --> omega pi0 --> pi0 pi0 gamma in c.m. Energy Range 920--1380 MeV at CMD-2
The cross section of the process e+ e- --> omega pi0 --> pi0 pi0 gamma has
been measured in the c.m. energy range 920-1380 MeV with the CMD-2 detector.
Its energy dependence is well described by the interference of the rho(770) and
rho'(1450) mesons decaying to omega pi0. Upper limits for the cross sections of
the direct processes e+ e- --> pi0 pi0 gamma, eta pi0 gamma have been set.Comment: Accepted for publication in PL
Study of the Process e+ e- ---> eta gamma in c.m. Energy Range 600-1380 MeV at CMD-2
The cross section of the process e+ e- ---> eta gamma has been measured in
the 600-1380 MeV c.m. energy range with the CMD-2 detector. The following
branching ratios have been determined:
B(rho ---> eta gamma) = (3.28 +- 0.37 +- 0.23) 10^{-4},
B(omega ---> eta gamma) = (5.10 +- 0.72 +- 0.34) 10^{-4},
B(phi --> eta gamma) = (1.287 +- 0.013 +- 0.063) 10^{-2}.
Evidence for the rho'(1450) ---> eta gamma decay has been obtained for the
first time.Comment: 17pages, 4 figures, submited to Phys.Lett.
Study of conversion decays phi->etae+e-, eta->e+e-g and eta->pi+pi-e+e- at CMD-2
Using 15.1 pb^{-1} of data collected by CMD-2 in the phi-meson energy range,
the branching ratios of the following conversion decays have been measured:
B(\phi\to\eta e^+e^-) = (1.14\pm0.10\pm0.06)\cdot10^{-4}, B(\eta\to
e^+e^-\gamma) = (7.10\pm0.64\pm0.46)\cdot10^{-3}, B(\eta\to\pi^+\pi^-e^+e^-) =
(3.7^{+2.5}_{-1.8}\pm0.3)\cdot10^{-4}. The upper limits for the following rare
conversion decays have been obtained at the 90% confidence level:
B(\phi\to\eta\mu^+\mu^-) < 9.4\cdot10^{-6}, B(\eta\to e^+e^-e^+e^-) <
6.9\cdot10^{-5}.Comment: 16 pages, 7 PostScript figures. To be published in Phys. Lett.