Published November 6, 2000 | Version v1
Journal article

Measurement of the Λ polarization in νμ charged current interactions in the NOMAD experiment

Creators

Description

The Λ polarization in νμ charged current interactions has been measured in the NOMAD experiment. The event sample (8087 reconstructed Λ 's) is more than an order of magnitude larger than that of previous bubble chamber experiments, while the quality of event reconstruction is comparable. We observe negative polarization along the W -boson direction which is enhanced in the target fragmentation region: Px(xF<0)=-0.21±0.04(stat)±0.02(sys) . In the current fragmentation region we find Px(xF>0)=-0.09±0.06(stat)±0.03(sys) . These results provide a test of different models describing the nucleon spin composition and the spin transfer mechanisms. A significant transverse polarization (in the direction orthogonal to the Λ production plane) has been observed for the first time in a neutrino experiment: Py=-0.22±0.03(stat)±0.01(sys) . The dependence of the absolute value of Py on the Λ transverse momentum with respect to the hadronic jet direction is in qualitative agreement with the results from unpolarized hadron-hadron experiments

Additional details

Identifiers

PII
S0550321300005034;

Publishing Information

Journal Title
Nuclear Physics. B
Journal Volume
588
Journal Issue
1-2
Journal Page Range
p. 3-36
ISSN
0550-3213
CODEN
NUPBBO

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Copyright
Copyright (c) 2000 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.