A Measurement of photon radiation in lepton pair events from Z0 decays

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 273 (1991) 338-354, 1991.
Inspire Record 319674 DOI 10.17182/hepdata.48520

We have measured the photon yield in lepton pair events recorded by the OPAL detector in a data sample corresponding to an integrated luminosity of 7.1 pb −1 at centre-of-mass energies between 88 GeV and 94 GeV. The results are compared to QED expectations for initial and final state photon radiation. No anomalous photon yield has been found, and stringent limits on the branching ratio for exotic radiative three body Z 0 decays into a photon and a pair of leptons are obtained. We also place limits on possible Z 0 decays into a photon and a resonance X with subsequent decays of X into a pair of leptons. Acollinear μ + μ − events with missing momentum along the beam direction are identified as events with hard initial state photon radiation and used to measure an average cross section of 15 ± 8 6 pb for e + e − annihilation into μ + μ − , in the so far untested range of centre-of-mass energies between 60 GeV and 84 GeV. This value is consistent with a cross section of 24 pb, expected from Z 0 and photon exchange.

1 data table

No description provided.


Measurement of the inclusive production of neutral pions and charged particles on the Z0 resonance

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 259 (1991) 199-208, 1991.
Inspire Record 314407 DOI 10.17182/hepdata.29468

We present a study of the inclusive production of neutral pions and charged particles from 112 000 hadronic Z 0 decays. The measured inclusive momentum distributions can be reproduced by parton shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results to e + e − data between √ s = 9 and 91 GeV, we findfind that the evolution of the spectra with center of mass energy is consistent with the QCD predictions.

6 data tables

No description provided.

Error is dominated by systematic uncertainties.

No description provided.

More…

Measurement of the Properties of the $\Omega$ Meson With a Cryogenic Magnetic Detector

Barkov, L.M. ; Vasserman, I.B. ; Vorobev, P.V. ; et al.
JETP Lett. 46 (1987) 164-167, 1987.
Inspire Record 255953 DOI 10.17182/hepdata.16910

None

1 data table

No description provided.


E+ E- PAIR PRODUCTION BY A SYNCHROTRON RADIATION PHOTON ON A COUNTER BEAM ELECTRON. (IN RUSSIAN)

Blinov, A.E. ; Bondar, A.F. ; Bukin, A.D. ; et al.
Yad.Fiz. 45 (1987) 1008-1014, 1987.
Inspire Record 256613 DOI 10.17182/hepdata.17424

None

3 data tables

Axis error includes +- 2/2 contribution (Error in counter efficiency determination).

Electron momentum distribution.

Electron-positron pairs mass distribution.


PROPERTIES OF D* PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
HRS-CP-83-3, 1983.
Inspire Record 192098 DOI 10.17182/hepdata.13343

None

2 data tables

D* FRAGMENTATION FUNCTION.

R VALUE IS RADIATIVELY CORRECTED (BUT NOT CROSS SECTION).


PRELIMINARY RESULTS FROM THE NEUTRAL DETECTOR AT VEPP-2M

Bukin, A.D. ; Vasserman, I.B. ; Vorobev, P.V. ; et al.
IYF-83-80, 1983.
Inspire Record 192041 DOI 10.17182/hepdata.37136

None

1 data table

Axis error includes +- 0.0/0.0 contribution (?////).


Experimental Limits on the Strength of Weak Neutral Currents in Lepton Pair Production at {PETRA} Energies

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 99 (1981) 281-286, 1981.
Inspire Record 156813 DOI 10.17182/hepdata.27121

The processes e + e − → e + e − and μ + μ − have been studied at PETRA using the JADE detector. The data, which were collected at s -values of up to 1300 GeV 2 have been analysed in terms of an electro-weak extension of QED to obtain values for the weak vector and axial vector couplings in the lepton sector. The values obtained agree with the predictions of the standard Salam-Weinberg model and the data are further analysed in terms of this model to obtain the limits 0.10 < sin 2 ϑ w < 0.40 (68% CL). The mass of the neutral weak gauge boson is deduced to be greater than 51 GeV/ c 2 .

3 data tables

No description provided.

No description provided.

No description provided.