Evidence for isovector neutron-proton pairing from high-spin states in N=Z Rb-74

• Published in: Physical review. C, Nuclear physics Vol. 67; no. 2: 021301
• Main Authors: O'Leary, CD, Svensson, CE, Frauendorf, SG, Afanasjev, AV, Appelbe, DE, Austin, RAE, Ball, GC, Cameron, JA, Clark, RM, Cromaz, M, Fallon, P, Hodgson, DF, Kelsall, NS, Macchiavelli, AO, Ragnarsson, Ingemar, Sarantites, D, Waddington, JC, Wadsworth, R
• Format: Journal Article
• Language: English
• Published: 01-02-2003
• Subjects: Fysik; Natural Sciences; Naturvetenskap; Physical Sciences
• ISSN: 0556-2813
• DOI: 10.1103/PhysRevC.67.021301

High-spin states in the odd-odd N=Z nucleus Rb-74(37)37 were studied using the Ca-40(Ca-40,alphanp) reaction. A previously observed odd-spin T=0 band has been extended to I-pi=(31(+)) and an even-spin T=0 band has been observed for the first time to I-pi=(22(+)); both have a pi(g(9/2))circle timesnu(g(9/2)) structure. A strongly coupled low-spin T=0,K=3 band has been interpreted as being based upon a pi[312]3/2 circle timesnu[312]3/2 configuration. Cranked relativistic Hartree-Bogoliubov calculations, which are corrected for the t=1 np-pair field by restoring isospin symmetry, reproduce the observed spectrum. These new results provide evidence for the existence of an isovector pair field that contains a neutron-proton component with the proper strength for ensuring isospin conservation.