An investigation of pairing correlations in diabatic configurations at high spin and large deformation: applications to the description of SD bands in Eu-143

The HFB cranked shell model is applied in an investigation of the selfconsistent pairing properties of the superdeformed (SD) bands in Eu-143. Results from a fully pairing and deformation selfconsistent mesh calculation of the properties of the most intense SD band in 143Eu are presented, as well as pairing selfconsistent calculations done at a fixed deformation close to the SD minimum for an excited SD configuration. The calculations are compared to unpaired calculations and to published experimental data. Fully diabatic configurations are studied and total energy surfaces are constructed for fixed values of the angular momentum. Other issues addressed include the development of the particle number distribution in the HFB wave function up to very high frequency, the consequences of using a fixed Fermi energy in high-spin calculations and the effects of the number of excited quasiparticles on the pairing properties of the superdeformed nucleus. (C) 2002 Elsevier Science B.V. All rights reserved.