Level structures of Rh 110,111,112,113 from measurements on Cf 252 Academic Article uri icon

abstract

  • Level schemes of [Formula Presented] and [Formula Presented] are proposed from the analysis of [Formula Presented] coincidence data from a [Formula Presented] spontaneous fission source with Gammasphere. These schemes have the highest excitation energies and spins yet established in these nuclei, as well as weakly populated bands not reported in earlier fission-[Formula Presented] work. From these data, information on shapes is inferred. By analogy with lighter [Formula Presented] odd-even isotopes, tentative spins and parities are assigned to members of several rotational bands. In this region triaxial nuclear shapes are known to occur, and we carried out calculations for [Formula Presented] and [Formula Presented] with the triaxial-rotor-plus-particle model. The [Formula Presented] bands of both nuclei, as well as lighter isotopes studied by others, show similar signature splitting. Our model calculations give a reasonable fit to the signature splitting, collective sidebands, and transition probabilities at near-maximum triaxiality with [Formula Presented]. For the [Formula Presented] band, experiment and model calculations do not fit well, which is accounted for by greater prolate deformation of the [Formula Presented] band, a case of shape coexistence. Our data on [Formula Presented] show no backbending and thus support the idea of the band crossing in the ground band of the odd-A neighbors being due to alignment of an [Formula Presented] neutron pair. In [Formula Presented] above the band crossing (spins [Formula Presented]) the ground band appears to split, with two similar branches. We consider the possibility that chiral doubling may be involved, but there are not enough levels to determine that. © 2004 The American Physical Society.

author list (cited authors)

  • Luo, Y. X., Wu, S. C., Gilat, J., Rasmussen, J. O., Hamilton, J. H., Ramayya, A. V., ... Gelberg, A.

citation count

  • 55

publication date

  • February 2004