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The nuclear structure of ${}^{99}$Tc was studied using the ${}^{98}$Mo${(}^{3}$He,$\mathrm{pn}\ensuremath{\gamma})$ reaction, which has populated most states in the nucleus below 2 MeV excitation energy. The proton exit channel was isolated from competing reaction channels by operating $\ensuremath{\gamma}$-ray detectors in coincidence with a large-solid-angle proton detector. The experiments included $\ensuremath{\gamma}$-ray excitation functions, $\ensuremath{\gamma}$-ray angular distributions, and $\ensuremath{\gamma}$-$\ensuremath{\gamma}$ coincidences. The results were interpreted using a particle-rotor model. The systematics of increasing deformations in odd-$A$ Tc nuclei are discussed.

The nuclear structure of {sup 101}Tc was studied using the {sup 100}Mo({sup 3}He,pn{gamma}) reaction, which has populated most states in the nucleus below 2 MeV excitation energy. The proton exit channel was isolated from competing reaction channels by operating {gamma}-ray detectors in coincidence with a large-solid-angle proton detector. The experiments included {gamma}-ray excitation functions, {gamma}-ray angular distributions, and {gamma}-{gamma} coincidences. The results were interpreted using a particle-rotor model. {copyright} {ital 1997} {ital The American Physical Society}

The nuclear structure of {sup 97}Tc was studied using the {sup 96}Mo({sup 3}He,{ital pn}{gamma}) reaction, which has populated most states in the nucleus below 2 MeV excitation energy. The proton exit channel was isolated from competing reaction channels by operating {gamma}-ray detectors in coincidence with a large-solid-angle proton detector. The experiments included {gamma}-ray excitation functions, {gamma}-ray angular distributions, and {gamma}-{gamma} coincidences. The results were interpreted using a particle-rotor model. {copyright} {ital 1996 The American Physical Society.}

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)

Levels in /sup 106/Ag have been studied using heavy-ion reactions. The experiments included ..gamma..-ray yields as a function of bombarding energy, ..gamma..-ray angular distributions, ..gamma..-ray linear polarizations, and three-detector ..gamma..-..gamma.. coincidence measurements. The decay scheme includes four collective bands with low-lying bandheads. The energies, ..gamma..-ray mixing ratios, and branching ratios of states in these bands are shown to be in good agreement with the corresponding quantities calculated using a two-particles-plus-rotor model at a small, symmetric deformation (delta=0.12). The Coriolis and recoil effects are explicitly included and a variable moment of inertia is used. The calculation also shows that the four bands have predominant configurations ..nu..(d/sub 5/2/)x..pi..(g/sub 9/2/), ..nu..(g/sub 7/2/)x..pi..(g/sub 9/2/), ..nu..(h/sub 11/2/)x..pi..(p/sub 1/2/), and ..nu..(h/sub 11/2/)x..pi..(g/sub 9/2/), respectively. The ..delta..I=1 and ..delta..I=2 level sequences in the bands can be understood on the basis of the positions of the neutron and proton Fermi surfaces in the respective Nilsson bases. Another band observed experimentally on a 10/sup -/ bandhead at 2.4416 MeV is thought to have a four-quasiparticle structure.

Several non-yrast states of both parities in $^{101}\mathrm{Pd}$ have been observed using three-detector $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence measurements following the reaction $^{92}\mathrm{Zr}(^{12}\mathrm{C}, 3n)^{101}\mathrm{Pd}$. Energy levels, $\ensuremath{\gamma}$-ray mixing ratios, and branching ratios are deduced from the data and compared with the results of a rotational model calculation. Five of the newly discovered states are identified as non-yrast members of rotational bands based on the $\frac{5}{{2}^{+}}$ and $\frac{11}{{2}^{\ensuremath{-}}}$ states.NUCLEAR STRUCTURE $^{92}\mathrm{Zr}(^{12}\mathrm{C}, 3n)^{101}\mathrm{Pd}$ at 48 MeV; measured ${I}_{\ensuremath{\gamma}}(\ensuremath{\theta})$, 3-detector $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coin, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ DCOQ. $^{101}\mathrm{Pd}$ deduced levels, $J$, $\ensuremath{\pi}$, $\ensuremath{\gamma}$ mixing ratios. Rotational model calculations, Coriolis, recoil, calculated levels, mixing ratios, branching ratios, half-lives.

The energy-level structure of /sup 99/Ru was studied using the /sup 98/Mo(/sup 3/He, 2n..gamma..)/sup 99/Ru reaction at a bombarding energy of 13 MeV, in an attempt to populate an extensive set of non-yrast states. The experiments included ..gamma..-ray excitation functions, ..gamma..-..gamma.. coincidence measurements, ..gamma..-ray angular distributions, and ..gamma..-ray linear polarization measurements. A large number of non-yrast states were observed, with angular momenta ranging from (1/2) to (17/2). The comparison of experimental energies and electromagnetic transition properties to the predictions of a particle-rotor model is presented. This interpretation suggests that several complete particle-core multiplets have been populated. The population of non-yrast states is attributable to the properties of the reaction rather than any details of the nuclear structure involved.

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 structure of $^{111}\mathrm{Ag}$ was studied using the $^{110}\mathrm{Pd}$${(}^{3}$He, pn\ensuremath{\gamma}) $^{111}\mathrm{Ag}$ reaction, which has populated an essentially complete set of low-energy states. The proton exit channel was isolated from competing reaction channels by operating \ensuremath{\gamma}-ray detectors in coincidence with a large-solid-angle proton detector. The experiments included \ensuremath{\gamma}-ray excitation functions, \ensuremath{\gamma}-ray angular distributions, and \ensuremath{\gamma}-\ensuremath{\gamma} coincidences. Four rotational bands have been identified. A symmetric particle-rotor model has been used to interpret these bands, and the model has identified other rotational features as well. A tentative interpretation of several nonrotational states is presented, suggesting that the mixing between rotational and nonrotational states is minimal.

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.