Tracking the neutron i13/2 orbital in the neutron-deficient polonium isotopes with the high-precision ISOLTRAP mass spectrometer at CERN-ISOLDE

Abstract

The measurements that will be presented investigate the neutron-deficient polonium isotopes in the region of A = 195 -199, with a special emphasis on 195Po and 197Po. These isotopes were produced at ISOLDE/CERN and delivered to the ISOLTRAP experiment where mass measurements and alpha-decay spectroscopy were performed. The decay-spectroscopy studies were carried out for the first time at ISOLTRAP with the support of the multi reflection time-of-flight mass spectrometer (MR-TOF MS). The masses of (195,197)g,mPo were measured precisely with Penning-trap mass spectrometry, from which the state ordering and the energy of the 13/2 states in 195,197Po were determined for the first time. Furthermore, the state ordering and the energy of the 13/2 state in lead, radon, and radium were obtained through alpha-decay chains. The new data complete the knowledge of the energy systematics in this region. The presented mass measurements provide information on the behaviour of the 13/2 states in the lead region near N = 104, which remain excited states. Additionally, 195Po half-life measurements were performed in isobarically pure conditions. The resulting 195gPo half-life value is in agreement with the one in the literature, with improving in the precision of the value, whereas the 195mPo half-life value is significantly smaller than the literature value.

Date of Award	1 Aug 2018
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Jonathan Billowes (Supervisor) & Kieran Flanagan (Supervisor)