Wraight, Kenneth
[90.0, 100.0]
Max results
Sort by Reverse order

Showing 3 of 63 results

A measurement of the Z0 invisible width by single photon counting.

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 50 (1991) 373-384, 1991.
Inspire Record 302586 DOI 10.17182/hepdata.14980

The OPAL detector at LEP is used to measure the branching ratio of theZ0 into invisible particles by measuring the cross section of single photon events ine+e− collisions at centre-of-mass energies near theZ0 resonance. In a data sample of 5.3 pb−1, we observe 73 events with single photons depositing more than 1.5 GeV in the electromagnetic calorimeter, with an expected background of 8±2 events not associated with invisibleZ0 decay. With this data we determine theZ0 invisible width to be 0.50±0.07±0.03 GeV, where the first error is statistical and the second systematic. This corresponds to 3.0±0.4±0.2 light neutrino generations in the Standard Model.

1 data table
Table 1

No description provided.


A Study of the recombination scheme dependence of jet production rates and of alpha-s (m(Z0)) in hadronic Z0 decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 49 (1991) 375-384, 1991.
Inspire Record 299833 DOI 10.17182/hepdata.15085

The error includes the experimental uncertainties (±0.003), uncertainties of hadronisation corrections and of the degree of parton virtualities to which the data are corrected, as well as the uncertainty of choosing the renormalisation scale.

9 data tables
Table 1

Jet production rates using the E0 recombination scheme.

Table 2

Jet production rates using the E recombination scheme.

Table 3

Jet production rates using the p0 recombination scheme.

More…

A Measurement of Global Event Shape Distributions in the Hadronic Decays of the $\Z^0$

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 47 (1990) 505-522, 1990.
Inspire Record 295613 DOI 10.17182/hepdata.15152

We present measurements of global event shape distributions in the hadronic decays of theZ0. The data sample, corresponding to an integrated luminosity of about 1.3 pb−1, was collected with the OPAL detector at LEP. Most of the experimental distributions we present are unfolded for the finite acceptance and resolution of the OPAL detector. Through comparison with our unfolded data, we tune the parameter values of several Monte Carlo computer programs which simulate perturbative QCD and the hadronization of partons. Jetset version 7.2, Herwig version 3.4 and Ariadne version 3.1 all provide good descriptions of the experimental distributions. They in addition describe lower energy data with the parameter values adjusted at theZ0 energy. A complete second order matrix element Monte Carlo program with a modified perturbation scale is also compared to our 91 GeV data and its parameter values are adjusted. We obtained an unfolded value for the mean charged multiplicity of 21.28±0.04±0.84, where the first error is statistical and the second is systematic.

9 data tables
Table 1

Corrected Thrust distribution.

Table 2

Corrected Major distribution.

Table 3

Corrected Minor distribution.

More…