Investigations of proton-neutron correlations close to the drip line
2010 (English)In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 82, no 2, 024307- p.Article in journal (Refereed) Published
Proton-neutron correlations in nuclei above the Z = 50 shell closure are investigated with the aim of understanding the behavior of the 2(+) and 4(+) states in Te and Xe isotopes, which remain at a rather constant energy as one approaches the shell closure at N = 50. Our calculations reveal that standard quasiparticle random phase approximation calculations, involving a quadrupole-quadrupole (QQ) interaction with constant strengths, cannot explain this feature. It is found that to reproduce the experimental data within this model one has to include a variable proton-neutron interaction. It turns out that an increased proton-neutron QQ interaction increases the collectivity (i.e., B(E2) values) when approaching the N = 50 region, whereas an increased proton-neutron pairing interaction decreases the collectivity. We thus conclude that the ratio between the B(E2) value and 2(+) energy is a "fingerprint" of proton-neutron collectivity and it should be determined in future experiments concerning light Te isotopes. Based on this criterion, we conclude that the available experimental data indicate an enhanced proton-neutron pairing interaction by approaching doubly magic Z = N = 20 and Z = N = 28 regions.
Place, publisher, year, edition, pages
2010. Vol. 82, no 2, 024307- p.
IdentifiersURN: urn:nbn:se:kth:diva-26867DOI: 10.1103/PhysRevC.82.024307ISI: 000280759100001ScopusID: 2-s2.0-77956154478OAI: oai:DiVA.org:kth-26867DiVA: diva2:373698
QC 201012012010-12-012010-11-292010-12-01Bibliographically approved