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arXiv · hep-ex/9906043

A Study of Spin Alignment of rho(770)+- and omega(782) Mesons in Hadronic Z Decays

The OPAL Collaboration·G. Abbiendi et al
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Abstract

The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons.

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The OPAL Collaboration, G. Abbiendi et al. 1999-06-30. A Study of Spin Alignment of rho(770)+- and omega(782) Mesons in Hadronic Z Decays. https://doi.org/10.1007/s100520050003

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