Comment on the hadronic decay of excited heavy quarkonia

Abstract

We make comments on ref.[Z.Phys. C73, 541 (1997)], and provide partial wave analysis to the decays of excited heavy S-wave $1^{-}$ quarkonia into the basic $1^{-}$ quarkonia state plus $\pi \pi$. It is revealed that there exist contributions of D-wave transition in ${\psi }^{\prime }⟶J/\psi \pi \pi$, ${\rm Y}(2S)⟶{\rm Y}(1S)\pi \pi$ and ${\rm Y}(3S)⟶{\rm Y}(1S)\pi \pi$ by using the data-fitting results in ref.[Z.Phys C73, 541 (1997)]. A possible experimental method to measure the D-wave directly is discussed.

7 pages, no figures, LaTeX file, To appear in The European Physical Journal (1998)