ISOLDE Seminar

Mass measurements of 49,50Sc, 73Br and 70As isotopes

by Ivan Kulikov (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))

High-precision mass spectrometry of radioactive isotopes is of high interest for scientific communities. Atomic masses provide direct insights on key nuclear structure phenomena, such as shell effects or onsets of deformation, and the way they evolve far from stability. In the field of astrophysics, the masses of exotic species constitute the most critical nuclear physics inputs in nucleosynthesis calculation.
The mass spectrometer ISOLTRAP, located at the radioactive ion-beam facility ISOLDE/CERN [1], pioneered the technique of on-line Penning-trap mass spectrometry of short-lived isotopes. During its thirty years of operation, over 400 short-lived nuclides have been measured. With the well-established Time-of-Flight Ion-Cyclotron-Resonance (ToF-ICR) mass measurement technique the achievable mass precision is on the level of 10-8. To improve the ISOLTRAP's ability to deliver purified beams to the measurement Penning trap, a Multi-Reflection Time-of-Flight Mass Separator (MR-ToF MS) has been constructed [2]. This device is routinely used as mass spectrometer as well. This contribution will present the specifics of both mass measurement techniques and recent data analysis of 70As, 49,50Sc and 73Br isotopes.
1. S. Kreim et al.// Nucl. Instrum. Meth. B. 2013.V.317. P.492-500
2. F. Wienholtz et al.// Int. J. Mass Spectr. 2017. V.421. P.285-293