Groom, Donald E.
E+ E- --> HADRONS
[5.0, 10.0]
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rivet Analysis
Cross-Sections and Event Topologies in e+ e- Annihilation at 13-GeV and 17-GeV Observed with the PLUTO Detector

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 81 (1979) 410-415, 1979.
Inspire Record 140294 DOI 10.17182/hepdata.45239

First results from the magnetic detector PLUTO at the new e + e − storage ring PETRA are shown. The ratio R of the cross section for hadron production to that for μ-pair production has been measured to be R = 5.0 ± 0.5 at 13 GeV and 4.3 ±0.5 at 17 GeV. Both values have an additional systematic error of 20%. The events show a typical 2-jet structure. The mean transverse momentum approaches a constant value with increasing energy implying a shrinkage of the jet opening angle.

2 data tables
Table 1

TAU HEAVY LEPTON PAIR CONTRIBUTIONS HAVE BEEN SUBTRACTED. R AT 13 AND 17 GEV, TOGETHER WITH SOME SELECTED LOWER ENERGY MEASUREMENTS FROM PLUTO AT DORIS.

Table 2

Data from earlier preprint DESY-79-06. NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


Measurement of the Parameters of the $\psi^{\prime\prime}$(3770) Resonance

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.D 21 (1980) 2716, 1980.
Inspire Record 142644 DOI 10.17182/hepdata.24185

We present a measurement of the cross section for hadron production by e+e− annihilation in the vicinity of the previously observed resonance near 3.77 GeV. The data are used to determine the parameters of the ψ(3770) resonance. The values found are: mass, 3764±5 MeV/c2, total width, 23.5±5 MeV, and partial width to electron pairs, 276±50 eV.

3 data tables
Table 1

THESE RESULTS ARE ALSO IN THE THESIS OF R. H. SCHINDLER, SLAC-219 (1979), THE RECORD OF WHICH CONTAINS THE TABULATED CROSS SECTIONS.

Table 2

BREIT-WIGNER RESONANCE PLUS BACKGROUND FIT TO RADIATIVELY CORRECTED DATA YIELDS RESONANCE MASS OF 3764 +- 5 MEV, TOTAL WIDTH OF 23.5 +- 5 MEV AND PARTIAL WIDTH TO ELECTRON PAIRS OF 276 +- 50 EV.

Table 3

PEAK CROSS SECTION FOR D MESON PAIR PRODUCTION AT PSI(3770) RESONANCE. J/PSI, PSI(3684) AND CONTINUUM BACKGROUND (R=2.5) SUBTRACTED.


rivet Analysis
The Measurement of R in e+ e- annihilation at center-of-mass energies between 7.2-GeV and 10.34-GeV

Blinov, A.E. ; Blinov, V.E. ; Bondar, A.E. ; et al.
Z.Phys.C 70 (1996) 31-38, 1996.
Inspire Record 364141 DOI 10.17182/hepdata.14321

The total cross section of the processe+e− →hadrons has been measured in the center-of-mass energy range between 7.25 and 10.34 GeV using the MD-1 detector at the VEPP-4 collider. The ratioR=σ(e+e− →hadrons)/σ(e+e− →μ+μ−) was found to be constant in this energy range with the average value of 3.58±0.02±0.14.

2 data tables
Table 1

Statistical errors only.

Table 2

Mean value of R in the range 7.25 to 10.34 GeV.


rivet Analysis
Measurement of R and determination of the charged particle multiplicity in e+ e- annihilation at s**(1/2) around 10-GeV

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Hamacher, T. ; et al.
Z.Phys.C 54 (1992) 13-20, 1992.
Inspire Record 319102 DOI 10.17182/hepdata.14708

We have measured theR value in non-resonante+e− annihilation using the ARGUS detector at the storage ring DORIS II. At a centre-of-mass energy\(\sqrt s= 9.36\) GeV the ratio of the hadronic cross-section to the μ-pair cross section in lowest order QED has been determined to beR=3.46±0.03±0.13. In addition, we have measured the charged-particle multiplicities in non-resonant hadron production at\(\sqrt s= 10.47\) GeV just below theB\(\bar B\) threshold and in ϒ (4S) resonance decays. For the average charged-particle multiplicities in continuum events and ϒ(4S)→B\(\bar B\) decays we obtain <n>cont=8.35±0.02±0.20 and <n>ϒ(4s)=10.81±0.05±0.23.

6 data tables
Table 1

Corrected for radiative effects and acceptance.

Table 2

Unfolded charged particle multiplicity distribution for continuum events.

Table 3

Unfolded charged particle multiplicity distribution for UPSILON(4S) events.

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The search for narrow resonances in the reaction e+ e- ---> hadrons at center-of-mass energy range between 7.23-GeV and 10.34-GeV

Blinov, A.E. ; Blinov, V.E. ; Beilin, M.V. ; et al.
Z.Phys.C 49 (1991) 239-243, 1991.
Inspire Record 316888 DOI 10.17182/hepdata.15083

The results of a search for narrow resonances ine+e− annihilation at centre-of-mass energies between 7.23 and 10.34 GeV are presented. The experiment was performed using the MD-1 detector at the VEPP-4 storage ring. The total luminosity integral of 16 pb−1 was taken. There is no evidence that new states exist. The upper limits on the leptonic widthΓee of possible resonances are less, by a factor of 10–80, than theΓee for the ϒ(1S) meson.

1 data table
Table 1

Average R value (excluding upsilon region).


A Determination of the Total Width of the $\Upsilon$ (9.46) Meson

Albrecht, H. ; Childers, R. ; Darden, C.W. ; et al.
Phys.Lett.B 93 (1980) 500-504, 1980.
Inspire Record 153029 DOI 10.17182/hepdata.6334

Using the DASP detector at the DESY storage ring DORIS we have continued measuring e + e − annihilations near and on the ϒ(9.46) resonance. From the cross sections for e + e − → μ + μ − and e + e − → hadrons we obtain a μ + μ − branching ratio for the ϒ(9.46) of (2.9 ± 1.3 ± 0.5) %, a leptonic width г ee = (1.35 ± 0.11 ± 0.22) keV and a total width of (47 −15 +37 keV.

2 data tables
Table 1

VISIBLE HADRONIC CROSS SECTION. PEAK VALUE AT UPSILON IS 10.1 +- 0.7 NB.

Table 2

No description provided.


rivet Analysis
Energy-energy Correlations in $e^+ e^-$ Annihilation Into Hadrons

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 292, 1981.
Inspire Record 156315 DOI 10.17182/hepdata.6228

Measurements of energy-energy correlations in hadronic final states produced in e + e − annihilation at c.m. energies between 7.7 and 31.6 GeV are presented. The data are compared to perturbative QCD predictions. Good qualitative agreement above 20 GeV c.m. energy is found. The importance of non-perturbative effects is discussed, as well as the detailed behaviour of the correlation near 180°.

6 data tables
Table 1

No description provided.

Table 2

OPPOSITE SIDE ENERGY-ENERGY CORRELATIONS NEAR 180 DEG.

Table 3

ENERGY-ENERGY CORRELATION INTEGRATED IN THE REGION 60 TO 120 DEG.

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rivet Analysis
A Measurement of the Branching Fraction of the Decay $\Upsilon$ (1s) $\to \tau^+ \tau^-$

The CLEO collaboration Giles, R. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.Lett. 50 (1983) 877, 1983.
Inspire Record 188803 DOI 10.17182/hepdata.20525

The branching fraction for the decay of the ϒ(1S) into τ paris has been measured to be (3.4±0.4±0.4)%. This result agrees with the previously measured branching ratio of the decay into muon pairs.

2 data tables
Table 1

VISIBLE CROSS SECTIONS IN THE PEAK.

Table 2

No description provided.


rivet Analysis
A Measurement of the Leptonic Branching Ratios of the $\Upsilon$ (1s), $\Upsilon$ (2s), and $\Upsilon$ (3s)

The CLEO collaboration Andrews, D. ; Avery, P. ; Berkelman, Karl ; et al.
Phys.Rev.Lett. 50 (1983) 807, 1983.
Inspire Record 188805 DOI 10.17182/hepdata.20536

Using the CLEO detector at the Cornell Electron Storage Ring, the authors have measured the leptonic branching fractions, Bμμ, of the ϒ(1S), ϒ(2S), and ϒ(3S) to be 2.7±0.3±0.3%, 1.9±1.3±0.5%, and 3.3±1.3±0.7%, respectively. Combining these values of Bμμ with previous measurements of the leptonic widths of these resonances, the authors find the total widths of the ϒ(1S), ϒ(2S), and ϒ(3S) to be 48±4±4, 27±17±6, and 13±4±3 keV.

1 data table
Table 1

No description provided.


phi MESON PRODUCTION AT THE UPSILON RESONANCES AND THE NEARBY CONTINUUM

Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
PRINT-83-0865, 1983.
Inspire Record 192222 DOI 10.17182/hepdata.11815

None

1 data table
Table 1

No description provided.