Configuration and bandhead spin assignments for the two-quasiparticle rotational bands in the neutron-rich nuclei Pm154,156

Abstract

The rotational bands in the neutron-rich nuclei 153−157 Pm are investigated by a particle-number conserving method. The kinematic moments of inertia for the 1-quasiparticle bands in odd-A Pm isotopes 153,155,157 Pm are reproduced quite well by the present calculation. By comparison between the experimental and calculated moments of inertia for the three 2-quasiparticle bands in the oddodd nuclei 154,156 Pm, their configurations and bandhead spins have been assigned properly. For the 2-quasiparticle band in 154 Pm, the configuration is assigned as π5/2 − [532] ⊗ ν3/2 − [521] (K π = 4 + ) with the bandhead spin I0 = 4 . In 156 Pm, the same configuration and bandhead spin assignments have been made for the 2-quasiparticle band with lower excitation energy. The configuration π5/2 + [413] ⊗ ν5/2 + [642] (K π = 5 + ) with the bandhead spin I0 = 5 is assigned for that with higher excitation energy.

Systematic study of odd-mass 151-161Pm and 154,156Pm isotopes using projected shell model *

“…The value of the quadrupole deformation parameter, ε 2 , is set as ~0.3 for all the nuclei under study, which is in agreement with the values given in Refs. [2][3][4]. In our meanfield Nilsson potential, which provides the optimal deformed basis, the hexadecapole deformation, ε 4 , has also been included and is set as ~ -0.090.…”

“…The Z= 61 Promethium (Pm) nuclei lie well within this region and provide a good testing ground for the theoretical models. These nuclei have attracted a considerable amount of research attention because of their large prolate deformation (β 2 ~0.3) [2][3][4]. Regarding the nuclear shell structures of neutron-rich [151][152][153][154][155][156][157][158][159][160][161] Pm nuclei, in particular, information about their excited states is rather scarce.…”

Rotational excitations in rare-earth nuclei: a comparative study within three cranking models with different mean fields and the treatments of pairing correlations

“…Note that the SLAP/PNC method has been built into theoretical approaches based on CSM with the Nilsson [28] and Woods-Saxon [90,91] potentials as well as on those based on relativistic [88] and non-relativistic [92] DFTs. These methods have been successful in the description of different nuclear phenomena in rotating nuclei such as odd-even differences in MOI [93], identical bands [94,95], nuclear pairing phase transition [96], antimagnetic rotation [46,[97][98][99], and high-K rotational bands in the rare-earth nuclei [100][101][102][103][104], and rotational bands in actinides [105][106][107][108][109]. Note that similar approaches to treat pairing correlations with exactly conserved particle number can be found in Refs.…”