Some Considerations on Global Symmetry

Abstract

If the recently discovered ${Y}^{*}$ state is related to the $T=\frac{3}{2}$, $J=\frac{3}{2}$ resonance in $\ensuremath{\pi}p$ scattering, global symmetry considerations should become relevant. In this paper, global symmetry is discussed with a view to understanding its group structure. Also discussed is a possibility of reconciling the conflict, pointed out by Pais, between certain experimental results and global symmetry. The partial widths of the ${Y}^{*}$ state are calculated and also those of the companion excited states ${Z}^{*}$ and ${\ensuremath{\Xi}}^{*}$. A generalization of the quantum number $G$ is discussed.