Core-coupled states and split proton-neutron quasi-particle multiplets in 122-126Ag

TL;DR

This study investigates the structure of neutron-rich silver isotopes 122-126Ag, revealing new isomeric states and interpreting excited states as core-coupled and split proton-neutron multiplets, supported by shell-model calculations.

Contribution

It provides the first observation of isomeric transitions in these isotopes and extends their level schemes, offering new insights into their nuclear structure.

Findings

Eight isomeric states observed in 122-126Ag

First detection of isomeric transitions in these isotopes

Shell-model calculations agree with experimental data

Abstract

Neutron-rich silver isotopes were populated in the fragmentation of a 136Xe beam and the relativistic fission of 238U. The fragments were mass analyzed with the GSI Fragment separator and subsequently implanted into a passive stopper. Isomeric transitions were detected by 105 HPGe detectors. Eight isomeric states were observed in 122-126Ag nuclei. The level schemes of 122,123,125Ag were revised and extended with isomeric transitions being observed for the first time. The excited states in the odd-mass silver isotopes are interpreted as core-coupled states. The isomeric states in the even-mass silver isotopes are discussed in the framework of the proton-neutron split multiplets. The results of shell-model calculations, performed for the most neutron-rich silver nuclei are compared to the experimental data.