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Even-A Pd nuclei were studied using the reactions /sup 92/,/sup 94/,/sup 96/Zr(/sup 13/C,3n..gamma..)/sup 102/,/sup 104/,/sup 106/Pd. The experiments included ..gamma..-ray yield as a function of energy, ..gamma..-ray angular distributions, ..gamma..-ray linear polarizations, and ..gamma..-..gamma.. coincidence measurements. A new treatment of ..gamma..-..gamma.. directional correlation from oriented nuclei, which combines data from all appropriate coincidence pairs to reduce uncertainties, has aided in determining multipolarities for 49 contaminated transitions. Extensive decay schemes are presented which include many high-angular-momentum, positive- and negative-parity states. In addition to the ground-state band, there appear to be three collective bands built on excited two-quasiparticle states. The measurements favor a slightly deformed rotor description of these nuclei over an interpretation in terms of a vibrational (interacting boson) model. (AIP)

States excited by the $^{99}\mathrm{Ru}(\ensuremath{\alpha},2n\ensuremath{\gamma})^{101}\mathrm{Pd}$, $^{88}\mathrm{Sr}(^{16}\mathrm{O},3n\ensuremath{\gamma})^{101}\mathrm{Pd}$, and $^{92}\mathrm{Zr}(^{12}\mathrm{C},3n\ensuremath{\gamma})^{101}\mathrm{Pd}$ reactions have been studied by measuring the $\ensuremath{\gamma}$-ray yield as a function of incident projectile energy, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidences, $\ensuremath{\gamma}$-ray angular distributions, and $\ensuremath{\gamma}$-ray linear polarizations. Three intense $\ensuremath{\gamma}$-ray cascades were observed. These cascades are produced by quasirotational bands built on the 5/${2}^{+}$, 7/${2}^{+}$, and 11/${2}^{\ensuremath{-}}$ intrinsic states of the nucleus. A decay scheme is given which includes states with energy up to 6488 keV and angular momentum up to 35/2. The quasirotational bands seen in $^{101}\mathrm{Pd}$ are similar to the bands in the adjacent even-even nuclei which suggests that this odd-$A$ nucleus can be described as a particle decoupled from an even-even core. A cascade of seven $\ensuremath{\gamma}$ rays in $^{102}\mathrm{Rh}$ was also observed following the $^{92}\mathrm{Zr}(^{12}\mathrm{C},p n)^{102}\mathrm{Rh}$ reaction.[NUCLEAR REACTION $^{99}\mathrm{Ru}(\ensuremath{\alpha},2n\ensuremath{\gamma})$, $E=16\ensuremath{-}24$ MeV; $^{92}\mathrm{Zr}(^{12}\mathrm{C},3n\ensuremath{\gamma})$, $E=45\ensuremath{-}56$ MeV; $^{88}\mathrm{Sr}(^{16}\mathrm{O},3n\ensuremath{\gamma})$, $E=56\ensuremath{-}64$ MeV; measured $\ensuremath{\sigma}(E)\ensuremath{\gamma}$, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coin, $\ensuremath{\sigma}(\ensuremath{\theta})\ensuremath{\gamma}$, linear $P$; deduced decay scheme, $J$, $\ensuremath{\pi}$.]

The linear polarization of ..gamma.. rays from the deexcitation of Cd isotopes A = 105 through 109 following (/sup 16/O,xn) reactions were measured using a Ge(Li) Compton polarimeter. The linear polarizations are used with ..gamma..-ray angular distributions to make unique-parity assignments and to remove ambiguity in angular-momentum values. With these measurements it is possible to identify many states in /sup 105hyphen109/Cd which are similar to states in Pd nuclei that have been interpreted as having one, two, or three quasiparticles coupled to a slightly deformed rotating core.

Levels in $^{105,107}\mathrm{Ag}$ have been studied using heavy-ion reactions. The experiments included $\ensuremath{\gamma}$-ray yields as a function of bombarding energy, $\ensuremath{\gamma}$-ray angular distributions, and three-detector $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence measurements. The positive-parity band based on the unique-parity ${g}_{\frac{9}{2}}$ orbital in both nuclei exhibits a $\ensuremath{\Delta}I=1$ character, unlike its counterpart ${h}_{\frac{11}{2}}$ band in Pd nuclei. The energy levels, $\ensuremath{\gamma}$-ray mixing ratios, branching ratios, and lifetimes in this band as well as in the ground-state negative-parity band are shown to be in good agreement with calculations using a particle-plus-rotor model at a small, symmetric deformation ($\ensuremath{\delta}=0.12$). The Coriolis and recoil effects are explicitly included and a variable moment of inertia is used. The low-lying "anomalous" $\frac{7}{{2}^{+}}$ state is also readily reproduced by this model. The calculation also shows that the $\ensuremath{\Delta}I=1$ nature of the positive-parity band results primarily from the fact that the Fermi surface is far from the $K=\frac{1}{2}$ state, whereas the transition properties are governed by the Coriolis mixing of the strong-coupled bands. Two bands built on the $\frac{17}{{2}^{\ensuremath{-}}}$ and $\frac{21}{{2}^{+}}$ states with high bandhead energies are thought to have three-quasiparticle configurations.NUCLEAR STRUCTURE $^{92}\mathrm{Zr}$($^{16}\mathrm{O}$,$p2n$)$^{105}\mathrm{Ag}$ at 60 MeV, $^{96}\mathrm{Zr}$($^{14}\mathrm{N}$, $3n$)$^{107}\mathrm{Ag}$ at 49 MeV: measured ${I}_{\ensuremath{\gamma}}(E(^{16}\mathrm{O}))$, ${I}_{\ensuremath{\gamma}}(E(^{14}\mathrm{N}))$, ${I}_{\ensuremath{\gamma}}(\ensuremath{\theta})$, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coin $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ DCOQ. $^{105,107}\mathrm{Ag}$ deduced levels, $J$, $\ensuremath{\pi}$, $\ensuremath{\gamma}$ mixing ratios. Rotational model calculations, Coriolis, calculated levels, mixing ratios, branching ratios, lifetimes. Ge(Li) detectors.

The energy level structure of 103 Pd was studied using the reactions 100 Ru(α, nγ) 103 Pd and 94 Zr( 12 C, 3nγ) 103 Pd. The experiments included the measurement of γ-ray yield as a function of incident projectile energy, γ-γ coincidence measurements, γ-ray angular distributions, and γ-ray linear polarization measurements. Two ΔI = 2 bands built on the 7 2 + and 11 1 − intrinsic states were observed. The ( 12 C, 3n) reaction was found to be much more effective than the (α, n) reaction in exciting these bands. A decay scheme is presented showing energies up to 6049 keV and spins up to 35 2 . Additional information relating to the coupling between the odd particle and the core is presented. A cascade of six γ-rays in 103 Rh was observed following the reaction 94 Zr( 12 C, p2nγ) 103 Rh.