Shape coexistence in neutron-deficient Pb nuclei probed by quadrupole moment measurements

• Published in: Physics letters. B Vol. 650; no. 2-3; pp. 141 - 147
• Main Authors: Ionescu-Bujor, M., Iordachescu, A., Mǎrginean, N., Ur, C.A., Bucurescu, D., Suliman, G., Balabanski, D.L., Brandolini, F., Chmel, S., Detistov, P., Gladnishki, K.A., Hübel, H., Mallion, S., Mǎrginean, R., Medina, N.H., Napoli, D.R., Neyens, G., Pavan, P., Ribas, R.V., Rusu, C., Turzó, K., Vermeulen, N.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 28.06.2007; Elsevier Science
• Subjects: Exact sciences and technology; Nuclear physics; Physics; Shape coexistence; Spectroscopic quadrupole moment; The physics of elementary particles and fields; 21.10.Ky; Spectroscopic quadrupole moment; 21.60.Ev; 27.80.+w; Shape coexistence; 21.10.Tg; Protons; Deformation; Interacting boson model; Neutrons; Angular distribution; Quadrupole moments; Half-life; Pairing; Isomers; Quadrupoles
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2007.05.002

The spectroscopic quadrupole moments of the 11− and 12+ isomers in 192,194Pb, described by the 3s1/2−21h9/21i13/2 intruder two-proton and 1i13/22 two-quasineutron configurations, respectively, have been determined by the method of time-differential observation of the γ-ray perturbed angular distribution. The derived values are |Qs|(12+,192Pb)=0.32(4) eb, |Qs|(11−,192Pb)=2.9(3) eb and |Qs|(11−,194Pb)=3.6(4) eb. The 8+ 2304 keV and 9− 2514 keV states in 192Pb have been identified as isomers, with half-lives of 3.9(3) and 3.3(2) ns, respectively. The experimental spectroscopic quadrupole moments for the 11− and 12+ isomers in neutron deficient Pb nuclei have been described in the framework of the pairing plus quadrupole model. The intrinsic quadrupole moments and deformation of the 11− isomers are compared with the predictions of mean-field and interacting boson models.