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High-spin states in the neutron-rich nuclei 172,173Yb have been populated in a 170Er(7Li,(p,d,t) xn) incomplete-fusion reaction and the emitted γ-radiation was detected with the GASP array. The signature partners of the 7/2+[633] rotational band of the odd- N 173Yb isotope have been newly established and were observed up to spin values of (45/2+) and (43/2+), respectively. The ground-state band of the even-even nucleus 172Yb has been observed up to a spin value of (22+). No band crossings were found in these bands. To explain this observation, it is proposed that the static pair field is absent, considering that the neutron odd-even mass differences reach for these nuclei very small values and that the band crossing is absent in cranked shell modell calculations without pairing. The results indicate, however, that strong dynamic correlations are still present. [ABSTRACT FROM AUTHOR]

High-spin states in 160,161,162Ho have been populated in the reactions 158,160Gd(7Li, xn) at 56 MeV. In all three isotopes the known rotational bands have been extended to significantly higher spin. In 160Ho, the band crossing in the π7/2- [523] × v11/2- [505] band has been observed for the first time. The sequences built on the proton 7/2- [523], 7/2+[404], 1/2+[411} and 1/2- [541] states in 161Ho have been extended up to spin 51/2-, 35/2+, 51/2+ and 41/2-, respectively, leading to the first observation of upbends in all four cases. In addition, a new band most probably belonging to this nucleus has been identified. In the most neutron-rich isotope 162Ho, the only known rotational band, which is built on the π7/2 [523] ⊗ v5/2+ [642] configuration, has been extended up to the 28- state. The properties of all observed bands are discussed and compared to the neighbouring isotopes. [ABSTRACT FROM AUTHOR]

During the last decade, as the experimental and computing means and techniques have rapidly evolved, the experimental investigation of the f7/2-shell nuclei has gained renewed interest. TheN = Z nuclei studied with the GASP array range from 44Ti to 52Fe. The results extended the knowledge of their structure up to high spins and excitation energies, above band terminations, where the competition with the charged-particles emission was initially thought to obscure the possibility of gamma-ray spectroscopy investigation. The paper highlights some of the most outstanding properties of these nuclei such as the nuclear rotation and backbending effects, band termination states, yrast traps, non-natural parity bands, competition between T = 0 and T = 1 pn pairing modes. [ABSTRACT FROM AUTHOR]

Recent inclusive measurements on multinucleon transfer reactions reveal important information on the interplay between single-particle and nucleon pair degrees of freedom. More detailed studies are being performed with the new magnetic spectrometer PRISMA, coupled to the CLARA γ-array. [ABSTRACT FROM AUTHOR]

High-spin states of the neutron-rich vibrational nucleus 114Cd have been studied using the incomplete fusion reaction 110Pd(7Li, p2n) and the GASP spectrometer in conjunction with the ISIS Si ball. About 50 new states with excitation energies up to 7 MeV and angular momentum I < (18+) were observed and for many of them, spin and parity could be firmly assigned. The band-like stuctures in 114Cd are compared to the corresponding ones in the even-even neighbour 112Cd. [ABSTRACT FROM AUTHOR]

The quadrupole interaction of high-spin isomers in 193Pb implanted into solid Hg cooled at a temperature T = 170 K has been investigated by the time-differential perturbed γ-ray angular-distribution method. Spectroscopic quadrupole moment values of &verbar;Qs&verbar; = 0.22(2) eb and 0.45(4) eb have been deduced for the 21/2- and 33/2+ three-neutron states, respectively. A much higher value &verbar;Qs&verbar; = 2.84(26) eb has been determined for the 29/2- isomer, the band head of a magnetic rotational band. [ABSTRACT FROM AUTHOR]

Multinucleon transfer cross sections in the 96Zr+40Ca system have been measured, in inverse kinematics, at bombarding energies ranging from the Coulomb barrier to ~25% below. Targetlike recoils have been identified in A, Z and velocity with the large solid angle magnetic spectrometer PRISMA. The experimental data for one- and two-neutron transfer channels have been compared with semiclassical microscopic calculations. For the two-neutron transfer channels the relevance of the transitions to the ground state and to the 0+ excited states of 42Ca are discussed by employing, for the reaction mechanism, the successive approximation. It is found that the transition to the 0+ state at ~6 MeV, whose wave function is dominated by the two neutrons in the 2p3/2 shell, is much larger than the ground state one. The comparison with the inclusive data reveals that transitions to states with high multipolarity and non-natural parity are important. This suggests that more complex two-particle correlations have to be incorporated in the treatment of the transfer process. [ABSTRACT FROM AUTHOR]