Study of the e+ e- --> eta gamma process with SND detector at the VEPP-2M e+ e- collider.

Achasov, M.N. ; Aulchenko, V.M. ; Beloborodov, K.I. ; et al.
Phys.Rev.D 74 (2006) 014016, 2006.
Inspire Record 717778 DOI 10.17182/hepdata.41804

In experiment with the SND detector at VEPP-2M $e^+e^-$ collider the $e^+e^-\to\eta\gamma$ cross section was measured in the energy range $E$=0.60--1.38 GeV with the integrated luminosity of 27.8 pb$^{-1}$. The measured cross section is well described by the vector meson dominance model with contributions from the $\rho(770)$, $\omega(783)$, $\phi(1020)$, $\rho^{\prime}(1465)$ resonances and agrees with results of previous measurements. The decay probabilities $\BR(\phi\to\eta\gamma)$, $\BR(\omega\to\eta\gamma)$ and $\BR(\rho\to\eta\gamma)$ were measured with the accuracies better than or comparable to the world averages.

2 data tables

Cross section from the ETA --> 3PI0 decay mode.

Cross section from the ETA --> PI+ PI- PI0 decay mode.


Study of the Processes e+ e- --> eta gamma, e+ e- --> pi0 gamma --> 3 gamma in the c.m. Energy Range 600--1380 MeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Aulchenko, V.M. ; Banzarov, V.Sh. ; et al.
Phys.Lett.B 605 (2005) 26-36, 2005.
Inspire Record 658856 DOI 10.17182/hepdata.41864

The processes e+ e- --> eta gamma, e+ e- --> pi0 gamma --> 3 gamma have been studied in the c.m. energy range 600--1380 MeV with the CMD-2 detector. The following branching ratios have been determined: Br(rho --> eta gamma) = (3.21 +- 1.39 +- 0.20)x 10^{-4}; Br(omega --> eta gamma) = (4.44 + 2.29 -1.83 +- 0.28)x 10^{-4}; Br(phi --> eta gamma) = (1.373 +- 0.014 +- 0.085)x 10^{-2}; Br(rho --> pi0 gamma) = (6.21 +1.28 - 1.18 +- 0.39)x 10^{-4}; Br(omega --> pi0 gamma) = (9.06 +- 0.20 +- 0.57)x 10^{-2}; Br(phi --> pi0 gamma) = (1.258 +- 0.037 +- 0.077)x 10^{-3};

2 data tables

Born cross section for the process E+ E- --> ETA GAMMA.

Born cross section for the process E+ E- --> PI0 GAMMA.


Measurement of $\phi$ Meson Radiative Decays at the Storage Ring Vepp-2m With the Neutral Detector

Druzhinin, V.P. ; Golubev, V.B. ; Ivanchenko, V.N. ; et al.
Phys.Lett.B 144 (1984) 136-140, 1984.
Inspire Record 202874 DOI 10.17182/hepdata.6570

Results of the first experiments with the Neutral Detector at the electron-positron storage ring VEPP-2M are presented. Branching ratios of the ø-meson radiative decays have been measured: B ( ø → ηγ )=(1.30±0.06)%, B ( ø → π 0 γ )=(0.130±0.013)%, their accuracy being several times higher than the world average. The width ratio is Γ(ø→ηγ) Γ(ø→π 0 γ)=(10±1) . Using the abovementioned quantities, the ω − ø mixing angle θ v =(38.3±0.2) ° , as well as the ratio between the effective magnetic moments of the s- and u-quarks, μ s μ u =(0.57±0.03) have been calculated.

8 data tables

CROSS SECTIONS IN THE PHI MESON PEAK (CORRECTED FOR RADIATIVE EFFECTS).

No description provided.

SAME AS FIG 2A, BUT KINEMATICAL RECONSTRUCTION ARE APPLIED. I.E. THE ENERGY- MOMENTUM CONSERVATIONS ARE USED TO IMPROVE THE ACCURACY OF PARTICLE ENERGIES AND ANGLES MEASURED IN DETECTOR.

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Study of the Process e+ e- ---> eta gamma in c.m. Energy Range 600-1380 MeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Anashkin, E.V. ; Aulchenko, V.M. ; et al.
Phys.Lett.B 509 (2001) 217-226, 2001.
Inspire Record 554522 DOI 10.17182/hepdata.27025

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.

1 data table

The measured Born cross section for the ETA GAMMA final state.