High spin states in ${}_{}{}^{109}{}_{}{}^{}\mathrm{Sn}$ have been established up to 9.1 MeV in excitation energy and to a spin of 43/$2^{\mathrm{-}}$ħ with the reaction ${}_{}{}^{94}{}_{}{}^{}\mathrm{Mo}$${(}^{19}$F,p3n${)}^{109}$Sn at a beam energy of 88 MeV. In-beam measurements involved γ-γ coincidences and directional correlation of oriented states. A negative-parity band consisting of stretched E2 transitions has been established. This band has been identified as the favored signature branch of the decoupled ${\mathrm{h}}_{11/2}$ neutron coupled to the deformed π(${\mathrm{g}}_{9/2}^{\mathrm{-}2}$⊗${\mathrm{g}}_{7/2}^2$) core configuration. © 1996 The American Physical Society.

• Received 16 January 1996

DOI:https://doi.org/10.1103/PhysRevC.54.2771