The $\eta$ - $\eta\prime$ mixing angle revisited

The value of the \(\eta\)-\(\eta\prime\) mixing angle \(\theta_P\) is phenomenologically deduced from a rather exhaustive and up-to-date analysis of data including strong decays of tensor and higher-spin mesons, electromagnetic decays of vector and pseudoscalar mesons, \(J/\psi\) decays into a vector and a pseudoscalar meson, and other transitions. A value of \(\theta_P\) between \(-17\)° and \(-13\)° is consistent with the present experimental evidence and the average \(\theta_P=-15.5^\circ\pm 1.3^\circ\) seems to be favoured.