Blocker, C.A.
R measurement
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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.


First Measurements of Hadronic Decays of the $Z$ Boson

The MARK-II collaboration Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 1558, 1989.
Inspire Record 282670 DOI 10.17182/hepdata.20044

We have observed hadronic final states produced in the decays of Z bosons. In order to study the parton structure of these events, we compare the distributions in sphericity, thurst, aplanarity, and number of jets to the predictions of several QCD-based models and to data from lower energies. The data and models agree within the present statistical precision.

5 data tables
Table 1

Corrected event shape distributions.

Table 2

Corrected event shape distributions.

Table 3

Corrected event shape distributions.

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A MEASUREMENT OF e+ e- ---> b anti-b FORWARD - BACKWARD CHARGE ASYMMETRY BETWEEN s**(1/2) = 52-GeV AND 57-GeV

The AMY collaboration Sagawa, H. ; Lim, J. ; Abe, K. ; et al.
Phys.Rev.Lett. 63 (1989) 2341, 1989.
Inspire Record 279824 DOI 10.17182/hepdata.19996

Using 123 multihadronic inclusive muon-production e+e− annihilation events at an average c.m. energy of 55.2 GeV, we extracted the forward-backward charge asymmetry of the e+e−→bb¯ process and the R ratio for bb¯ production. We used an analysis method in which the behavior of the c quark and lighter quarks is assumed, with only that of the b quark left indeterminate. The results, Ab=-0.72±0.28(stat)±0.13(syst) and Rb=0.57±0.16±0.10, are consistent with the standard model.

2 data tables
Table 1

Asymmetry in BOTTOM quark production.

Table 2

Ratio of BOTTOM quark production to total hadron cross section (R value).


rivet Analysis
Measurement of the Total Hadronic Cross-section in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

The MARK-II collaboration Von Zanthier, Christoph ; de Boer, W. ; Grindhammer, Guenter ; et al.
Phys.Rev.D 43 (1991) 34-45, 1991.
Inspire Record 295286 DOI 10.17182/hepdata.22852

A precise measurement of the ratio R of the total cross section e+e−→hadrons to the pointlike cross section e+e−→μ+μ− at a center-of-mass energy of 29.0 GeV is presented. The data were taken with the upgraded Mark II detector at the SLAC storage ring PEP. The result is R=3.92±0.05±0.09. The luminosity has been determined with three independent luminosity monitors measuring Bhabha scattering at different angular intervals. Recent calculations of higher-order QED radiative corrections are used to estimate the systematic error due to missing higher-order radiative corrections in the Monte Carlo event generators.

1 data table
Table 1

No description provided.


rivet Analysis
MEASUREMENTS OF R FOR e+ e- ANNIHILATION AT TRISTAN

The AMY collaboration Kumita, T. ; Sagawa, H. ; Auchincloss, Priscilla S. ; et al.
Phys.Rev.D 42 (1990) 1339-1349, 1990.
Inspire Record 294525 DOI 10.17182/hepdata.22908

The ratio R of the total cross section for e+e− annihilation into hadrons to the lowest-order QED cross section for e+e−→μ+μ− has been measured for center-of-mass energies ranging from 50 to 61.4 GeV. If we allow for an overall shift of —4.9%, about 1.5 times our estimated normalization error, the results are consistent with the standard-model predictions.

1 data table
Table 1

Error quoted contains point-to-point systematics. There is also an additional 3.2 pct systematic error.


Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Averill, D. ; et al.
Phys.Rev.Lett. 63 (1989) 2173, 1989.
Inspire Record 281818 DOI 10.17182/hepdata.20033

We have measured the mass of the Z boson to be 91.14±0.12 GeV/c2, and its width to be 2.42−0.35+0.45 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.46±0.10 GeV, corresponding to 2.8±0.6 neutrino species, with a 95%-confidence-level upper limit of 3.9.

1 data table
Table 1

No description provided.


Initial Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 724, 1989.
Inspire Record 280007 DOI 10.17182/hepdata.20034

We have measured the mass of the Z boson to be 91.11±0.23 GeV/c2, and its width to be 1.61−0.43+0.60 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.62±0.23 GeV, corresponding to 3.8±1.4 neutrino species.

1 data table
Table 1

Data now superceded.


MEASUREMENTS OF THE e+ e- TOTAL HADRONIC CROSS-SECTION AND A DETERMINATION OF M(Z) AND LAMBDA (MS)

The AMY collaboration Mori, T. ; Nozaki, T. ; Blanis, D. ; et al.
Phys.Lett.B 218 (1989) 499-507, 1989.
Inspire Record 276653 DOI 10.17182/hepdata.29847

The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .

1 data table
Table 1

No description provided.


Measurements of r and a Search for Heavy Quark Production in e+ e- Annihilation at s**(1/2) = 50-GeV and 52-GeV

The AMY collaboration Sagawa, H. ; Mori, T. ; Abe, K. ; et al.
Phys.Rev.Lett. 60 (1988) 93, 1988.
Inspire Record 251270 DOI 10.17182/hepdata.20143

The ratio R of the cross section for e+e− annihilation into hadronic final states to the QED cross section for muon-pair production is measured to be 4.34±0.45±0.30 and 4.23±0.20±0.21 at c.m. energies of 50 and 52 GeV, respectively. From these values of R and an analysis of the event shapes we deduce a 95%-confidence-level upper limit for the production rate of new heavy charge +23e or −13e quarks to be 0.19 units of R.

1 data table
Table 1

No description provided.