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Excited states in 124Xe were populated in the reaction 82Se(48Ca, 6 n)124Xe and γ -ray coincidence relationships were measured with the Gammasphere spectrometer. Two new bands are observed and several of the previously known bands are extended in the high- as well as in the low-spin region. Two irregular high-spin structures are also added. The irregularities are a fingerprint of a transition from collective to non-collective behaviour. Configuration assignments to the new structures are proposed on the basis of systematics and by comparing experimental properties with calculations within the framework of the cranking model. [ABSTRACT FROM AUTHOR]

An activation technique was used to investigate relative yields of fission products from the reaction 232Th(n, f ) for neutron energies between 1.3 and 1.8MeV covering the region around the first hyperdeformed resonances. Intensities of characteristic γ-ray transitions were analyzed to search for changes in the mass distribution for neutron energies corresponding to the resonances and below the resonances. Relative increases in yield between 7 and 23% are observed for A ≈ 100 and 132 in the resonance region around 1.6MeV. It is proposed that the yield enhancement of daughter nuclei of the preformed fragments 132Sn and 101Zr arises from cold fission of a di-cluster configuration. The experimental results support theoretical predictions for the existence of hyperdeformed octupole shapes based on the di-nuclear configuration 132Sn + 101Zr. [ABSTRACT FROM AUTHOR]

High-spin states in 79Rb were populated in the reaction $\mathrm{^{63}Cu \ensuremath(^{19}F, p2n) ^{79}Rb}$ at E( beam) = 60 MeV. The lifetimes of the excited states of the $\pi \ensuremath g_{\frac{9}{2}}$ positive-parity yrast band and of the $\pi \ensuremath p_{\frac{3}{2}}$ negative-parity band in 79Rb were measured by the Doppler Shift Attenuation Method. The deduced transition quadrupole moments Qt are found to have a decreasing trend with rotational frequency for both the bands, consistent with those found experimentally in neighbouring nuclei. [ABSTRACT FROM AUTHOR]

The first excited 2+ states in neutron-rich 54,56,58Cr were populated by relativistic Coulomb excitation and B (E2, 2 → 0+) values were determined for 56Cr and 58Cr. The B(E2) values show a minimum for 56Cr providing evidence for a subshell closure at N=32. [ABSTRACT FROM AUTHOR]

High-spin states in 78Kr have been studied via the 63Cu (19F, 2p2n)78Kr reaction at a beam energy of 60 MeV using the Indian National Gamma Array (INGA). In this nucleus, lifetimes have been measured upto the I π=22+ level in the yrast positive-parity band and upto the I π=15- level in the negative-parity band using the Doppler Shift Attenuation Method (DSAM). The deduced transition quadrupole moments Qt's are found to decrease with rotational frequency for both the bands. [ABSTRACT FROM AUTHOR]

High-spin states in161Lu were investigated using the EUROBALL spectrometer. A previously known triaxial superdeformed band has been extended to higher spins and a new band with similar characteristics has been discovered. Comparison to systematically occurring wobbling bands in Lu isotopes strongly suggests that these two bands represent thenw = 0 and 1 wobbling excitations in161Lu. [ABSTRACT FROM AUTHOR]

We report on four recent results concerning the population and the decay of superdeformed states, namely the structure of excited superdeformed states in 194Hg, the search for fine structure of the last superdeformed transitions in 194Pb, the primary decay-out strength analysis in 194Hg and, as a consequence of this, the possibility of using the decay-out as a tool to study order-to-chaos properties of normally deformed states. [ABSTRACT FROM AUTHOR]

High-spin states of the nucleus 163Lu have been populated through the fusion-evaporation reaction 139La(29Si, 5n) with a beam energy of 157 MeV. In addition to the two lowest excited triaxial strongly deformed (TSD) bands, recently interpreted as one- and two-phonon wobbling excitations, a third excited TSD band has been firmly established decaying to the yrast TSD band. The assignment of this band as a three-quasiparticle band shows together with the normal deformed (ND) level scheme the presence not only of shape coexistence between ND and TSD structures, but also an interplay of wobbling and quasiparticle excitations in the triaxial strongly deformed potential well of 163Lu. [ABSTRACT FROM AUTHOR]

High-spin states in161Lu and162Lu have been investigated using the GASP γ-ray spectrometer array. Excited states in these nuclei have been populated through the100Mo(65Cu, xn) reaction at a beam energy of 260 MeV. Four presumably triaxial superdeformed bands, three in162Lu and one in161Lu, have been observed. This is the first evidence for triaxial superdeformation in the two isotopes. [ABSTRACT FROM AUTHOR]

First evidence is presented for triaxial superdeformation in 170Hf. High-spin states in this nucleus have been investigated in a γ-ray coincidence measurement using the EUROBALL spectrometer array. A new band was discovered which has moments of inertia that are very similar to the ones of triaxial superdeformed bands in neighbouring Hf and Lu nuclei. The intensities with which these bands are populated are different from what may be expected from calculated potential-energy minima. [ABSTRACT FROM AUTHOR]

The mass distribution of nuclides produced in the reaction 232Th(n,f) with neutron energies below and within the resonance region was investigated using the activation method. The results confirm the theoretical predictions of the existence of hyperdeformed octupole shapes in 233Th. [ABSTRACT FROM AUTHOR]