The energy level structures of even-even tellurium and odd-odd iodine and antimony nuclei: tellurium-114, tellurium-116, iodine-114, and antimony-114.

摘要

Nuclear structure studies were performed on the even-even nuclides {dollar}sp{lcub}114,116{rcub}{dollar}Te following the {dollar}betasp+{dollar}/EC decay of {dollar}sp{lcub}114,116{rcub}{dollar}I, respectively, to investigate the possible role of particle-hole intruder structures previously observed in other even-even nuclei near the Z = 50 shell. Studies were also carried out for odd-odd {dollar}sp{lcub}rm 114m,g{rcub}{dollar}I and {dollar}sp{lcub}114{rcub}{dollar}Sb by observing the isomeric decay of {dollar}sp{lcub}rm 114m{rcub}{dollar}I and the {dollar}betasp+{dollar}/EC decay of {dollar}sp{lcub}114{rcub}{dollar}Te, respectively, to characterize the low-energy proton-neutron multiplet structures of these nuclei. Gamma-ray and electron singles data, gamma-gamma and electron-gamma coincidence data, as well as multiscaled gamma singles data were collected at the on-line mass separator UNISOR at Oak Ridge National Laboratory. The magnetic moment of the ground state of {dollar}sp{lcub}114{rcub}{dollar}Sb was measured by an integral online low-temperature nuclear orientation experiment carried out at the UNISOR Nuclear Orientation Facility.; Evidence for intruder admixtures was found for both {dollar}sp{lcub}114{rcub}{dollar}Te and {dollar}sp{lcub}116{rcub}{dollar}Te, although it is apparent that the influence of these configurations is decreasing with decreasing neutron number below the middle of the neutron shell. Among the new states proposed for these nuclei are the entire second phonon multiplet for both {dollar}sp{lcub}114{rcub}{dollar}Te and {dollar}sp{lcub}116{rcub}{dollar}Te, and most of the members of the third phonon quintuplet in {dollar}sp{lcub}114{rcub}{dollar}Te.; The decay of the 5.7(5) s isomer in {dollar}sp{lcub}114{rcub}{dollar}I has been characterized as being a 5{dollar}sp-{dollar} state at 237.6 keV decaying to an intermediate 2{dollar}sp-{dollar} state at 103.2 keV, decaying then to a 1{dollar}sp+{dollar} ground state. Both the isomer and the ground state have been found to populate levels in {dollar}sp{lcub}114{rcub}{dollar}Te.; The magnetic dipole moment of the ground state of {dollar}sp{lcub}114{rcub}{dollar}Sb was measured to be 1.72(8) n.m. and indicates an appreciable change in the ground state configuration from a nearly pure {dollar}pi{dollar}d{dollar}sb{lcub}5/2{rcub}nu{dollar}s{dollar}sb{lcub}1/2{rcub}{dollar} configuration to one that is substantially admixed with the {dollar}pi{dollar}d{dollar}sb{lcub}5/2{rcub}nu{dollar}g{dollar}sb{lcub}7/2{rcub}{dollar} configuration. Ten levels below 500 keV and 12 levels above 500 keV are proposed based on spectroscopic studies. The number and position of the low-energy levels are consistent with those expected from the available single-particle couplings.