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.


Experimental study of the processes e+ e- --> phi --> eta gamma, pi0 gamma at VEPP-2M.

Achasov, M.N. ; Berdyugin, A.V. ; Bozhenok, A.V. ; et al.
Eur.Phys.J.C 12 (2000) 25-33, 2000.
Inspire Record 524221 DOI 10.17182/hepdata.43394

The processes$e^+e^-\rightarrow\eta\gamma, \pi^0\gamma\rightarrow 3\gamma$were studied in the SND experiment at the VEPP-2M collider in the energy region of the

2 data tables

Results of energy scan of the cross section.

Cross sections for PHI production and decay into the two states from a fit to the data at the peak.


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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New Measurements with the Orsay electron-Positron Storage Ring of the Radiative Decay Modes of the phi-Meson

Cosme, G. ; Courau, A. ; Dudelzak, B. ; et al.
Phys.Lett.B 63 (1976) 352-356, 1976.
Inspire Record 99833 DOI 10.17182/hepdata.27640

The radiative decay models of the φ-meson have been studied: e + e − → φ → ηγ →3 γ ; e + e − → φ → π o γ →3 γ . Cross sections σ φ → ηγ →3 γ and σ φ → π o γ →3 γ have been measured at five energies in the φ-meson energy region and clearly show the φ-resonance in the ηγ → 3 γ mode as well as in the π o γ → 3 γ mode. From a Breit-Wigner fit to the experimental data the values of the branching ratios are deduced: B φ → ηγ = (1.5 ± 0.4) × 10 −2 ; B φ → π o γ = (1.4 ± 0.5) × 10 −3 .

1 data table

REMOVING RADIATIVE CORRECTIONS, THE PHI PEAK CROSS SECTIONS ARE 66 NB +- 25 PCT <ETA GAMMA> AND 6.5 NB +- 30 PCT <PI0 GAMMA>.