Hadronic transitions ofD-wave quarkonium

The decays Υ(1D)→Υππ are calculated within the framework of the multipole expansion in QCD. Using a description of the conversion of gluons into pions based on soft-pion theorems, we find Γ(Υ(1 ${}_{}{}^3{}_{}{}^{}D_J^{}{}_{}{}^{}$)→Υππ)=0.07 keV; the rates are identical for J=1,2,3. The smallness of these rates means that the ${}_{}{}^3{}_{}{}^{}\mathrm{D}$ states can probably only be observed using their electric-dipole transitions Υ(1D)→Υ(1P)γ. .AE