A study of spin alignment of \(\rho(770)^{\pm}\) and \(\omega(782)\) mesons in hadronic Z\(^0\) decays

The helicity density matrixelements \(\rho_{00}\) of \(\rho(770)^{\pm}\) and \(\omega(782)\) mesonsproduced in Z\(^0\) decays have been measured using the OPAL detector at LEP. Over the measured mesonenergy 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 \(\rho^{\pm}\) and the \(\omega\) are 0.373 \(\pm\) 0.052 and 0.142 \(\pm\) 0.114, respectively. These results are compared to measurements of other vector mesons.