Characterizing the atomic mass surface beyond the proton drip line via a-decay measurements of the s1/2 ground state of 165Re and the h11/2 isomer in 161Ta

TL;DR

This study investigates alpha decay chains from 173Au, revealing new isomeric states and decay pathways, and provides insights into the atomic mass surface beyond the proton drip line through detailed decay measurements.

Contribution

It reports the first observation of prompt gamma rays feeding 173Au's ground state and clarifies the decay of 161Ta as an isomeric state, advancing understanding of nuclear structure near the proton drip line.

Findings

Identification of a previously unreported activity as decay of 165Re

First observation of prompt gamma rays feeding 173Au ground state

Determination of excitation energy and Q-value for 161Ta decay

Abstract

The a-decay chains originating from the s1/2 and h11/2 states in 173Au have been investigated following fusion-evaporation reactions. Four generations of a radioactivities have been correlated with 173Aum leading to a measurement of the a decay of 161Tam. It has been found that the known a decay of 161Ta, which was previously associated with the decay of the ground state, is in fact the decay of an isomeric state. This work also reports on the first observation of prompt g rays feeding the ground state of 173Au. This prompt radiation was used to aid the study of the a-decay chain originating from the s1/2 state in 173Au. Three generations of a decays have been correlated with this state leading to the observation of a previously unreported activity which is assigned as the decay of 165Reg. This work also reports the excitation energy of an a-decaying isomer in 161Ta and the Q-value of the decay of 161Tag.