High-precision measurements of low-lying isomeric states in $^{120-124}$In with JYFLTRAP double Penning trap

TL;DR

This study used high-precision double Penning trap mass spectrometry to measure low-lying isomeric states in neutron-rich indium isotopes, providing detailed excitation energies and confirming state presence through decay spectroscopy.

Contribution

The paper presents the first high-precision measurements of isomeric states in $^{120-124}$In using JYFLTRAP, resolving states and comparing results with theoretical models.

Findings

Resolved isomeric states in $^{121,123,124}$In.

Measured excitation energies with high precision.

Confirmed presence of certain states via decay spectroscopy.

Abstract

Neutron-rich $^{120-124}$In isotopes have been studied utilizing the double Penning trap mass spectrometer JYFLTRAP at the IGISOL facility. Using the phase-imaging ion-cyclotron-resonance technique, the isomeric states were resolved from ground states and their excitation energies measured with high precision in $^{121,123,124}$In. In $^{120,122}$In, the $1^+$ states were separated and their masses were measured while the energy difference between the unresolved $5^+$ and $8^-$ states, whose presence was confirmed by post-trap decay spectroscopy was determined to be $\leq15$ keV. In addition, the half-life of $^{122}$Cd, $T_{1/2} = 5.98(10)$ s, was extracted. Experimental results were compared with energy density functionals, density functional theory and shell-model calculations.