Polarization and forward - backward asymmetry of Lambda baryons in hadronic Z0 decays - INSPIRE

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Polarization and forward - backward asymmetry of Lambda baryons in hadronic Z0 decays

OPAL

Collaboration

Jul, 1997

22 pages

Published in:

Eur.Phys.J.C 2 (1998) 49-59

e-Print:

hep-ex/9708027 [hep-ex]

DOI:

10.1007/s100520050123

Report number:

CERN-PPE-97-104

Experiments:

CERN-LEP-OPAL

View in:

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Abstract:

The longitudinal polarization, the transverse polarization, and the forward-backward asymmetry of Lambda baryons have been measured using a sample of 4.34 million hadronic Z^0 decays collected with the OPAL detector at LEP between 1990 and 1995. These results are important as an aid to the understanding of hadronization mechanisms. Significant longitudinal polarization has been observed at intermediate and high momentum. For x_E = 2 E_{Lambda}/\sqrt{s}) > 0.3, the longitudinal polarization has been measured to be -32.9 +/- 5.5(stat) +/- 5.2(syst)%. We have observed no transverse polarization. A significant forward-backward asymmetry has been measured and can be described by a JETSET model.

electron positron: colliding beams
electron positron: annihilation
Z0: electroproduction
Z0: hadronic decay
Lambda: polarization
polarization: longitudinal
angular distribution: asymmetry
model: hadronization
OPAL
experimental results

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