Gu, Y.F
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Observation of the Production of $\eta$ Mesons in Two Photon Collisions

Weinstein, A. ; Antreasyan, D. ; Gu, Y.F. ; et al.
Phys.Rev.D 28 (1983) 2896, 1983.
Inspire Record 192651 DOI 10.17182/hepdata.23791

Using 2674 nb−1 of data taken at s from 5.00 to 7.25 GeV with a trigger sensitive to decays of lower-mass particles produced in two-photon collisions, we have observed 56±12 events consistent with the reaction e+e−→e+e−η, η→γγ. Background has been subtracted using separated-beam data. We obtain Γγγ(η)=0.56±0.16 keV and the pseudoscalar-nonet mixing angle θP=−17.6°±3.6°.

1 data table
Table 1

No description provided.


rivet Analysis
Hadron Production in $e^+ e^-$ Annihilation From $\sqrt{s}=5$-{GeV} to 7.4-{GeV}

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
SLAC-PUB-5160, 1990.
Inspire Record 294419 DOI 10.17182/hepdata.18758

None

4 data tables
Table 1

Data from Run 1. There is an additional overall systematic uncertainty of 5.2 pct.

Table 2

Data from Run 2. There is an additional overall systematic uncertainty of 5.2 pct.

Table 3

Average R value.

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rivet Analysis
Measurements of Total Hadronic and Inclusive $D^*$ Cross-sections in $e^+ e^-$ Annihilations Between 3.87-{GeV} and 4.5-{GeV}

Osterheld, A. ; Hofstadter, R. ; Horisberger, R. ; et al.
SLAC-PUB-4160, 1986.
Inspire Record 238081 DOI 10.17182/hepdata.18759

None

2 data tables
Table 1

R measurement.

Table 2

D* cross sections.


Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
Phys.Lett.B 110 (1982) 82-86, 1982.
Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables
Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.


Measurement of Inclusive $\eta$ Production in $e^+ e^-$ Interactions Near Charm Threshold

Partridge, Richard ; Peck, C. ; Porter, F. ; et al.
Phys.Rev.Lett. 47 (1981) 760, 1981.
Inspire Record 165255 DOI 10.17182/hepdata.3280

We have measured the inclusive cross section for η production in e+e− interactions near charm threshold using the Crystal Ball detector. No pronounced structure in the energy dependence is observed. By comparing cross sections above and below charm threshold we obtain the limits (90% confidence limit): R(e+e−→FF¯X)RB(F→ηx)<0.15−0.32 (for Ec.m. from 4.0 to 4.5 GeV), RB(D→ηx)<0.13. Our results are inconsistent with a previous report of a large energy dependence of the η cross section ascribed to the crossing of the FF* and F*F* production thresholds.

7 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

Table 2

THE 4.028 GEV DATA ARE NOT INCLUDED IN THE 4.005-4.082 GEV BIN. Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

Table 3

AT FIXED ENERGIES.

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A Direct measurement of the pseudoscalar decay constant, f(D(s))

The BES collaboration Bai, J.Z. ; Bardon, O. ; Blum, Ira K. ; et al.
Phys.Rev.Lett. 74 (1995) 4599-4602, 1995.
Inspire Record 382314 DOI 10.17182/hepdata.50375

The Beijing Spectrometer (BES) experiment has observed purely leptonic decays of the Ds meson in the reaction e+e−→Ds+Ds− at a c.m. energy of 4.03 GeV. Three events are observed in which one Ds decays hadronically to φπ, K¯*0K, or K¯0K, and the other decays leptonically to μνμ or τντ. With the assumption of μ−τ universality, values of the branching fraction, B(Ds→μνμ)=(1.5−0.6−0.2+1.3+0.3)%, and the Ds pseudoscalar decay constant, fDs=(4.3−1.3−0.4+1.5+0.4)×102 MeV, are obtained.

2 data tables
Table 1

No description provided.

Table 2

In this table CONST is the pseudoscalar decay constant, f_[D/S].


Search for psi(2S) production in e+ e- annihilations at 4.03-GeV

The BES collaboration Bai, J.Z. ; Bian, J.G. ; Blum, I. ; et al.
Phys.Rev.D 57 (1998) 3854-3859, 1998.
Inspire Record 468969 DOI 10.17182/hepdata.22270

A search is performed for the production of the ψ(2S) in e+e− annihilation at a center-of-mass energy of 4.03 GeV using the BES detector operated at the Beijing Electron Positron Collider (BEPC). The kinematic features of the reconstructed ψ(2S) signal are consistent with its being produced only in association with an energetic photon resulting from initial state radiation (ISR). Limits are placed on ψ(2S) production from the decay of unknown charmonia or metastable hybrids that might be produced in e+e− annihilations at 4.03 GeV. Under the assumption that the observed cross section for ψ(2S) production is due entirely to ISR, the partial width Γee of the ψ(2S) is measured to be 2.07±0.32keV.

1 data table
Table 1

PSI(UNSPEC) is considered as a new 3D2 charmonium state. CHI/C(UNSPEC) is considered as any unknown charmonium state. EXOTIC is considered as a metastable hybrid.


Measurement of the pseudoscalar decay constant, f(D).

The BES collaboration Bai, J.Z. ; Bardon, O. ; Blum, Ira K. ; et al.
SLAC-PUB-7147, 1996.
Inspire Record 421008 DOI 10.17182/hepdata.18760

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
A Measurement of J / psi decay widths

The BES collaboration Bai, J.Z. ; Chen, G.P. ; Chen, H.F. ; et al.
Phys.Lett.B 355 (1995) 374-380, 1995.
Inspire Record 39870 DOI 10.17182/hepdata.28500

The cross sections for e + e − → hadrons, e + e − , μ + μ − have been measured in the vicinity of the J Ψ resonance using the BES detector operated at BEPC. The partial widths for J Ψ to hadrons, electrons, muons and the total width have been determined to be Γ h = 74.1 ± 8.1 keV, Γ e = 5.14 ± 0.39 keV, Γ μ = 5.13 ± 0.52 keV, and Γ = 84.4 ± 8.9 keV, respectively.

1 data table
Table 1

No description provided.


rivet Analysis
Measurement of the Total Cross Section for Hadronic Production by e+e- Annihilation at Energies between 2.6-5 Gev

The BES collaboration Bai, J.Z. ; Ban, Y. ; Bian, J.G. ; et al.
Phys.Rev.Lett. 84 (2000) 594-597, 2000.
Inspire Record 505323 DOI 10.17182/hepdata.41611

Using the upgraded Beijing Spectrometer (BESII), we have measured the total cross section for $e^+e^-$ annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6 and 5.0 GeV. Values of $R$, $\sigma(e^+e^-\to {hadrons})/\sigma(e^+e^-\to\mu^+\mu^-)$, are determined.

1 data table
Table 1

Data are corrected for acceptance and radiative effects.