Excited states inY86

High spin states in ${}_{}{}^{86}{}_{}{}^{}\mathrm{Y}$ were studied through the ${}_{}{}^{85}{}_{}{}^{}\mathrm{Rb}(\alpha ,3\mathrm{}\mathrm{n})$ reaction at energies between 30 and 55 MeV, using techniques of in-beam $\gamma$-ray spectroscopy. Eight levels were observed on top of the $J^{\pi }=8^{+}$ (218.3 keV) metastable state which are connected by $\gamma$ rays in cascade and five levels decaying to the $J^{\pi }=5^{-}$ (208.1 keV) excited state. The former were interpreted in terms of the weak coupling of the proton $\pi \left(1\mathrm{}{g}_{\frac{9}{2}}\right)$ and the neutron hole $v^{-1\mathrm{}}\left(1\mathrm{}{g}_{\frac{9}{2}}\right)$ coupled to the ${}_{}{}^{86}{}_{}{}^{}\mathrm{Sr}$ excited states on the basis of the shell model.