Nucleon pair approximation description of the low-lying structure of ${}^{108,109}$Te and ${}^{109}$I

Abstract

The low-lying level schemes and electromagnetic transitions of ${}^{109}$Te, ${}^{109}$I, and the neighboring even-even nucleus ${}^{108}$Te, are calculated within the framework of the $SD$-pair approximation of the nuclear shell model. Good agreement is obtained between the calculated results and experimental data. The favored components of low-lying bands are discussed in the collective nucleon-pair subspace. The weak-coupling picture shown in these nuclei and its relationship with residual quadrupole-quadrupole interaction between valence protons and neutrons are analyzed.

Comments: printer-friendly version, 6 figures and 5 tables, 10 pages, to be published in PRC