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The cross section of the $e^+e^-\to\omega\pi^0\to\pi^0\pi^0\gamma$ reaction was measured by the SND detector at VEPP-2M $e^+e^-$ collider in the energy range from threshold up to 1.4 GeV. Results of the cross section fitting by the sum of $\rho$, $\rho^{\prime}$ and $\rho^{\prime\prime}$ contributions are presented.

1 data table match query

Table 1

Only statistical errors are presented.

rivet Analysis
Cross section of the reaction $e^+ e^- \to \pi^+\pi^-\pi^+\pi^- $ below 1 GeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Anashkin, E.V. ; Arpagaus, M. ; et al.

Phys.Lett.B 475 (2000) 190-197, 2000.

Inspire Record 511375 DOI 10.17182/hepdata.27052

Using 3.07 ${pb}^{-1}$ of data collected in the energy range 0.60-0.97 GeV by CMD-2, about 150 events of the process $\epm \to \pch$ have been selected. The energy dependence of the cross section agrees with the assumption of the $a_1(1260) \pi$ intermediate state which is dominant above 1 GeV. For the first time \fourpi events are observed at the $\rho$ meson energy. Under the assumption that all these events come from the $\rho$ meson decay, the value of the cross section at the $\rho$ meson peak corresponds to the following decay width: \Gamma(\rho^0 \to \fourpi) = (2.8 \pm 1.4 \pm 0.5) {keV} or to the branching ratio B(\rho^0 \to \fourpi) = (1.8 \pm 0.9 \pm 0.3) \cdot 10 ^{-5}.

1 data table match query

Table 1

Measured cross section.

OBSERVATION OF THE PROCESS E+ E- ---> GAMMA GAMMA GAMMA GAMMA

Vasserman, I.B. ; Golubev, V.B. ; Dolinsky, S.I. ; et al.

JETP Lett. 44 (1986) 634-637, 1986.

Inspire Record 241072 DOI 10.17182/hepdata.16909

None

4 data tables match query

Table 1

No description provided.

Table 2

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Table 3

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Investigation of the reaction pi- p ---> eta n at momenta up to 40-GeV/c

The Serpukhov-CERN collaboration Apel, W.D. ; Bertolucci, E. ; Bushnin, Yu.B. ; et al.

Sov.J.Nucl.Phys. 25 (1977) 194-197, 1977.

Inspire Record 118649 DOI 10.17182/hepdata.19079

None

1 data table match query

Table 1

No description provided.

Reaction $\pi^- p \to \eta^\prime n$ in the 15-{GeV}/$c$ - 40-{GeV}/$c$ Momentum Range

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.

Phys.Lett.B 83 (1979) 131, 1979.

Inspire Record 141023 DOI 10.17182/hepdata.49657

Measurements were made of the cross section of the reactions π − p → ν ′(958)n, η ′ → 2 γ at momenta at 15, 20, 25, 30 and 40 GeV/c. The experiment was carried out on the IHEP 70 GeV accelerator using the 648 channel hodoscope spectrometer NICE for γ-ray detection. A total of 6000 η′ mesons were recorded. A sharp drop is seen in the differential cross section for t → 0. The dependences of the differential cross sections for the π − p → η ′n and π − p → η n on t are identical. On the basis of the ratio of the cross sections for these reactions at t = 0, i.e. R( η′ n ) t=0 = 0.55 ± 0.06 , the singlet-octet mixing angle for pseudoscalar mesons was determined to be β = −(18.2 ± 1.4)°.

2 data tables match query

Table 5

DATA AT 20, 25 AND 30 GEV/C SUMMED AND NORMALIZED TO THE CROSS SECTION AT 25 GEV/C.

Table 7

DATA AT 20, 25 AND 30 GEV/C SUMMED AND NORMALIZED TO THE CROSS SECTION AT 25 GEV/C.

RECENT RESULTS OF EXPERIMENTS WITH THE NEUTRAL DETECTOR AT VEPP-2M

Druzhinin, V.P. ; Dubrovin, M.S. ; Eidelman, S.I. ; et al.

IYF-84-93, 1984.

Inspire Record 202875 DOI 10.17182/hepdata.37143

None

1 data table match query

Table 1

'AXION' IS NEUTRAL BOSON WHICH HAS MASS < 200 MEV. IT IS ASSUMED THAT NEITHER THIS BOSON NOR THE PRODUCTS OF ITS DECAY ARE DETECTED.

First physical results from SND detector at VEPP-2M.

The SND collaboration Achasov, M.N. ; Beck, M.G. ; Beloborodov, K.I. ; et al.

BUDKER-INP-1997-78, 1997.

Inspire Record 450009 DOI 10.17182/hepdata.50302

The paper describes experiments with the SND detector at VEPP-2M collider, carried out during the period from October 1995 until June 1997. The total integrated luminosity of 6.4 pb^{-1} was collected in the energy range 2E=0.4-1.4 GeV (MHAD97 experiment), corresponding to 4*10^5 mu^+ mu^- pairs produced. Preliminary results of the 1996 phi-meson experiment (FI96) are presented. The total number of phi-mesons produced is 4*10^6. New data on rare decays of phi and eta (550) mesons, in particular B(phi -> eta gamma) = (1.30+-0.06+-0.07)%, B(phi -> pi^0 pi^0 gamma) = (1.1+-0.2)*10^{-4}, (M_{pi^0 pi^0} > 800 MeV), B(phi -> f^0 gamma) = (4.7+-1.0)*10^{-4}, B(phi -> eta pi^0 gamma) = (1.3+-0.5)*10^{-4}, B(phi -> eta' gamma) < 1.7*10^{-4}, B(phi -> 2 pi^0 ) < 6*10^{-4} were obtained.

4 data tables match query

Table 1

No description provided.

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ASYMMETRY MEASUREMENTS IN PION PHOTOPRODUCTION BY POLARIZED PHOTONS IN THE ENERGY RANGE FROM 250-MeV TO 600-MeV

Angular distributions of the asymmetry of the gamma p ---> p pi0 reaction with the gamma-quanta energies of 400, 450, 500, 550, 650 mev

Angular dependence of the asymmetry of the cross section for the reaction $\gamma$p $\rightarrow$ $\Delta^{++}\pi^{-}$ at a photon energy 650 MeV

rivet Analysis
The process e+ e- --> omega pi0 --> pi0 pi0 gamma up to 1.4-GeV.

rivet Analysis
Cross section of the reaction $e^+ e^- \to \pi^+\pi^-\pi^+\pi^- $ below 1 GeV at CMD-2

OBSERVATION OF THE PROCESS E+ E- ---> GAMMA GAMMA GAMMA GAMMA

Investigation of the reaction pi- p ---> eta n at momenta up to 40-GeV/c

Reaction $\pi^- p \to \eta^\prime n$ in the 15-{GeV}/$c$ - 40-{GeV}/$c$ Momentum Range

RECENT RESULTS OF EXPERIMENTS WITH THE NEUTRAL DETECTOR AT VEPP-2M

First physical results from SND detector at VEPP-2M.