$\gamma$-ray linear polarization measurements have been used to locate negative parity states in the even-odd isotopes ${}_{}{}^{99,101,103}{}_{}{}^{}\mathrm{Pd}$. A Compton polarimeter based on two Ge(Li) coaxial detectors was used. Collective bands ($I={\frac{11}{2}}^{-}, {\frac{15}{2}}^{-}, {\frac{19}{2}}^{-}, \dots$) built on ${\frac{11}{2}}^{-}$ states were observed in ${}_{}{}^{101}{}_{}{}^{}\mathrm{Pd}$ and ${}_{}{}^{103}{}_{}{}^{}\mathrm{Pd}$. Many negative parity states were also observed in ${}_{}{}^{99}{}_{}{}^{}\mathrm{Pd}$, but they do not appear to be part of a similar collective band. These polarization measurements also confirm many angular momentum assignments which previously had been made using systematic arguments.

NUCLEAR REACTIONS ${}_{}{}^{90,92,94}{}_{}{}^{}\mathrm{Zr}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, 3n)$, $E=48-56\mathrm{}$ MeV; measured linear polarization of $\gamma$ rays; parities and multipole mixing ratios in ${}_{}{}^{99,101,103}{}_{}{}^{}\mathrm{Pd}$ transitions deduced.

• Received 24 February 1975

DOI:https://doi.org/10.1103/PhysRevC.12.499