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Measurement of charm production in two photon processes using inclusive lepton events at TRISTAN

The AMY collaboration Aso, T. ; Miyata, H. ; Sasaki, T. ; et al.
Phys.Lett.B 363 (1995) 249-258, 1995.
Inspire Record 401053 DOI 10.17182/hepdata.38520

Measurements of open charm production in photon-photon collisions made with the AMY detector at TRISTAN are reported. Charmed hadrons were identified by detecting the high momentum muons or electrons from their semileptonic decays. The data sample corresponds to an integrated luminosity of 275 pb −1 at an average center of mass energy of 58 GeV. Results are presented in the form of cross sections of inclusive leptons from charm for both muons and electrons. The measured cross section is 1.8 standard deviations higher than theoretical predictions based on the direct and photon-gluon fusion process, where the mass of charm quark is assumed to be 1.6 GeV.

3 data tables

rivet Analysis
The Electron Spectrum From $B$ Meson Decays

The Crystal Ball collaboration Wachs, K. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 42 (1989) 33, 1989.
Inspire Record 263581 DOI 10.17182/hepdata.45204

The Crystal Ball Collaboration has measured the energy spectrum of electrons from semileptonicB meson decays at thee+e− storage ring DORIS II. Branching ratios and weak mixing angles of the Kobayashi-Maskawa matrix are determined using several models for the hadronic matrix elements. We obtain the branching ratio for semileptonic.B decays to charmed states BR(B→evXc)=(11.7±0.4±1.0)%. Our result for the corresponding Kobayashi-Maskawa matrix element is |Vcb|=0.052±0.006. The model dependence of both results is included in the error. We have not observed semileptonicB decays to non-charmed mesons. Analyzing the measured electron spectrum above 2.4 GeV, where nob→c decays contribute, we find BR(B→evXu)/BR(B→evXc)<6.5% at the 90% confidence level. This corresponds to an upper limit |Vub/Vcb|<0.21.

1 data table
Table 1

The errors quoted are statistical only.


Prompt Electron Production From Delco at {PEP}

The DELCO collaboration Pal, T. ; Atwood, W.B. ; Barish, B.C. ; et al.
Phys.Rev.D 33 (1986) 2708, 1986.
Inspire Record 226886 DOI 10.17182/hepdata.23516

We report final results on prompt electron production in hadronic events from e+e− annihilations at √s =29 GeV, obtained with the DELCO detector at the SLAC storage ring PEP. We find the semielectronic branching ratios of charm and bottom quarks to be B(c→se+νe)=(11.6−0.9 +1.1)% and B(b→ce−ν¯e)=(14.9−1.9 +2.2)% respectively. These results, from the complete data set, are consistent with an earlier analysis of partial data and indicate hard fragmentation functions for both c and b quarks, with mean values 〈zc〉=0.59±0.04 and 〈zb〉=0.72±0.05. The errors indicated here are a combination of statistical and systematic uncertainties.

4 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 2

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 3

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

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PROMPT ELECTRON PRODUCTION IN ELECTRON - POSITRON ANNIHILATIONS AT 29-GeV

Koop, Dale E. ;
CALT-68-1149, 1984.
Inspire Record 201707 DOI 10.17182/hepdata.50118

None

7 data tables
Table 1

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

Table 2

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

Table 3

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

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