Comment onP-state dominance in the hadronic production of narrow resonances

Abstract

We show that the process $\mathrm{gg}\to P\to \mathrm{psion}+a$ ($a=\mathrm{hadron} or \gamma$, $g=\mathrm{gluon}$) explains the observed features in the hadronic production of $\frac{\psi }{J}$ and ${\psi }^{\prime }$ and the absence of hadronic production of ${\psi }^{\prime \prime }$, ${\psi }^{\prime \prime \prime }$, etc.