Inclusive production of the eta and omega mesons in Z decays, and the muonic branching ratio of the omega

摘要

The inclusive production of the eta and omega(782) mesons is measured in the pi(+)pi(-)pi(0) decay mode in hadronic Z decays and compared to model predictions. The analysis is based on 4 million hadronic Z decays recorded by the ALEPH detector between 1991 and 1995. The eta production rate for x(rho) p(meson)/p(beam) > 0.10 is found to be 0.355 +/- 0.01(stat) +/- 0.024(sys) per event, and the omega production rate for x(p) > 0.05 is measured as 0.585 +/- 0.019(stat) +/- 0.033(sys) per event. The branching ratio for omega --> mu(+)mu(-) investigated. A total of 18.1 +/- 5.9 events are observed, from which the muonic branching ratio is measured for the first time to be BR(omega --> mu(+)mu(-)) + 9.0 +/- 2.9(stat) 1.1(sys)) x 10(-5). (C) 2002 Elsevier Science B.V. All rights reserved. References: 26