Ablikim, M.
E+ E- --> HADRONS
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Results from pluto at petra

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
1 (1979) 343-349, 1979.
Inspire Record 148976 DOI 10.17182/hepdata.45229

None

1 data table
Table 1

No description provided.


rivet Analysis
Study of Electron - Positron Collisions at the Highest {PETRA} Energy

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Lett.B 85 (1979) 463-466, 1979.
Inspire Record 141976 DOI 10.17182/hepdata.27332

We report on the results of the study of e + e − collisions at the highest PETRA energy of √ s = 31.57 GeV, using the 4π sr, electromagnetic and calorimetric detector Mark J. Based on 88 hadron events, and an integrated luminosity of 243 nb −1 we obtain R = σ (e + e − → hadrons)/ σ (e + e − → μ + μ − ) = 4.0 ± 0.5 (statistical) ± 6 (systematic). The R value, the measured thrust distribution and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

CORRECTIONS FOR TWO-PHOTON PROCESSES, TAU HEAVY LEPTON PRODUCTION AND INITIAL STATE RADIATIVE CORRECTIONS HAVE BEEN APPLIED.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 31.57 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


RESULTS FROM DASP ON E+ E- ANNIHILATION BETWEEN 3.1-GEV AND 5.2-GEV

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.
Z.Phys.C 1 (1979) 233-256, 1979.
Inspire Record 145403 DOI 10.17182/hepdata.16476

This paper summarizes the measurements one+e− annihilation performed by the DASP Collaboration in the energy range between 3.1 and 5.2 GeV. The following topics are covered: total cross section, production and two body decays of the narrow resonances, radiative decays of theJ/ψ and ψ′ resonances and evidence for theX(2.82), ψ′ cascade decays, inclusive η production and evidence for theF meson, semileptonic decays of charmed mesons and properties of the heavy lepton.

5 data tables
Table 1

THESE DATA ON R WERE PUBLISHED IN R. BRANDELIK ET AL., PL 76B, 361 (1978), THE RECORD OF WHICH HAS TABULATED CROSS SECTIONS WITH AND WITHOUT THE TAU HEAVY LEPTON CONTRIBUTION.

Table 2

OBSERVATION OF J/PSI RESONANCE.

Table 3

OBSERVATION OF PSI(3700)0 RESONANCE.

More…

MULTI - HADRON PRODUCTION IN E+ E- ANNIHILATION AT 1.45-GEV - 1.61-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Pallotta, M. ; et al.
Lett.Nuovo Cim. 25 (1979) 5-12, 1979.
Inspire Record 145867 DOI 10.17182/hepdata.37370

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Measurement of Leptonic Branching Ratios of the $\Upsilon$ (9.46)

The PLUTO collaboration Berger, Christoph ; Lackas, W. ; Raupach, F. ; et al.
Z.Phys.C 1 (1979) 343, 1979.
Inspire Record 140818 DOI 10.17182/hepdata.16475

The electronic width Γee and the muonic branching ratioBμμ=Γμμ/Γtot of the Γ(9.46) have been measured as Γee=(1.33±0.14) andBμμ=(2.2±2.0)%. From these values a lower limit of Γtot<23keV for the total width of the Γ(9.46) is obtained.

2 data tables
Table 1

THE DATA POINTS INCLUDE 10 PCT OF THE TAU HEAVY LEPTON PAIR EVENTS.

Table 2

NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


Observation of a Narrow Resonance Formed in e+ e- Annihilation at 9.46-GeV

The Pluto collaboration Berger, Christoph ; Lackas, W. ; Raupach, F. ; et al.
Phys.Lett.B 76 (1978) 243-245, 1978.
Inspire Record 130053 DOI 10.17182/hepdata.27457

An experiment using the PLUTO detector has observed the formation of a narrow, high mass, resonance in e + e − annihilations at the DORIS storage ring. The mass is determined to be 9.46±0.01 GeV which is consistent with that of the Upsilon. The gaussian width σ is observed as 8±1 MeV and is equal to the DORIS energy resolution. This suggests that the resonance is a bound state of a new heavy quark-antiquark pair. An electronic width Γ ee =1.3±0.4 keV was obtained. In standard theoretical models, this favors a quark charge assignment of 1 3 .

1 data table
Table 1

No description provided.


rivet Analysis
Observation of a Resonance in e+ e- Annihilation Just Above Charm Threshold

Rapidis, Petros A. ; Gobbi, B. ; Luke, D. ; et al.
Phys.Rev.Lett. 39 (1977) 526, 1977.
Inspire Record 119979 DOI 10.17182/hepdata.20971

We observe a resonance in the total cross section for hadron production in e+e− annihilation at a mass of 3772±6 MeV/c2 having a total width of 28±5 MeV/c2 and a partial width to electron pairs of 370±90 eV/c2.

2 data tables
Table 1

BEFORE ANY RADIATIVE CORRECTIONS.

Table 2

AFTER APPLYING ALL RADIATIVE CORRECTIONS.


rivet Analysis
Properties of Hadron Final States in e+ e- Annihilation at 13-GeV and 17-GeV Center-Of-Mass Energies

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 83 (1979) 261-266, 1979.
Inspire Record 140303 DOI 10.17182/hepdata.27352

We have observed e + e − hadrons at C.M. energies of 13 GeV and 17 GeV at PETRA using the TASSO detector. We find R (13 GeV) = 5.6 ± 0.7 and R (17 GeV) = 4.0 ± 0.7. The additional systematic uncertainty is 20%. Comparing inclusive charged hadron spectra we observe scaling between 5 GeV and 17 GeV for x = p / p beam > 0.2; however the 13 GeV cross section is above the 17 GeV cross section for smaller x . This may be due to copious bb̄ production. The events become increasingly jet like at high energies as evidenced by a shrinking sphericity distribution with increasing energy.

2 data tables
Table 1

TAU HEAVY LEPTON CONTRIBUTION SUBTRACTED.

Table 2

THESE DATA FOR S*D(SIG)/DX AT 13 AND 17 GEV ARE INCLUDED IN THE RECORD OF R. BRANDELIK ET AL., PL 89B, 418 (1980).


rivet Analysis
Total Cross-section for Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 3.6-{GeV} and 5.2-{GeV}

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.
Phys.Lett.B 76 (1978) 361, 1978.
Inspire Record 129715 DOI 10.17182/hepdata.27431

The total cross section for e + e − annihilation into hadronic final states between 3.6 and 5.2 GeV was measured by the nonmagnetic inner detector of DASP, which has similar trigger and detection efficiencies for photons and charged particles. The measured difference in R = σ had / σμμ between 3.6 GeV and 5.2 GeV is ΔR = 2.1 ± 0.3. We observe three peaks at cm energies of 4.04, 4.16 and 4.417 GeV, the parameters of which, when interpreted as resonances, are given.

2 data tables
Table 1

EXCLUDING CONTRIBUTION OF TAU HEAVY LEPTON.

Table 2

INCLUDING CONTRIBUTION OF TAU HEAVY LEPTON.


rivet Analysis
Observation of a Resonance at 4.4-GeV and Additional Structure Near 4.1-GeV in e+ e- Annihilation

Siegrist, J. ; Abrams, G.S. ; Boyarski, A. ; et al.
Phys.Rev.Lett. 36 (1976) 700, 1976.
Inspire Record 108144 DOI 10.17182/hepdata.21093

We observe a resonancelike structure in the total cross section for hadron production by e+e− colliding beams at a mass of 4414 ± 7 MeV having a total width Γ=33±10 MeV. From the area under this resonance, we deduce the partial width to electron pairs to be Γee=440±140 eV. Further structure of comparable width is present near 4.1 GeV.

1 data table
Table 1

No description provided.