0000000000065131
AUTHOR
M. De Saint Simon
High-accuracy mass determination of unstable cesium and barium isotopes
Direct mass measurements of short-lived Cs and Ba isotopes have been performed with the tandem Penning trap mass spectrometer ISOLTRAP installed at the on-line isotope separator ISOLDE at CERN. Typically, a mass resolving power of 600 000 and an accuracy of $\delta \mbox{m} \approx 13$ keV have been obtained. The masses of $^{123,124,126}$Ba and $^{122m}$Cs were measured for the first time. A least-squares adjustment has been performed and the experimental masses are compared with theoretical ones, particularly in the frame of a macroscopic-microscopic model.
High-accuracy mass determination of neutron-rich rubidium and strontiumiIsotopes
The penning-trap mass spectrometer ISOLTRAP, installed at the on-line isotope separator ISOLDE at CERN, has been used to measure atomic masses of $^{88,89,90m,91,92,93,94}$Rb and $^{91- 95}$Sr. Using a resolving power of R $\!\scriptstyle\approx$1 million a mass accuracy of typically 10 keV was achieved for all nuclides. Discrepancies with older data are analyzed and discussed, leading to corrections to those data. Together with the present ISOLTRAP data these corrected data have been used in the general mass adjustment.
Direct mass measurements of unstable rare earth isotopes with the ISOLTRAP mass spectrometer
Abstract Direct mass measurements of neutron deficient rare earth isotopes in the vicinity of 146 Gd were performed for the first time with the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Since ISOL-facilities deliver these isotopes with a large amount of isobaric contamination, these measurements became possible only after the installation of a new cooler trap which acts as an isobar separator. To date more than 40 isotopes of the elements Pr, Nd, Pm, Sm, Eu, Dy, and Ho have been measured with a typical accuracy of δm ≈ 14 keV. Some of these isotopes provide an important anchor for many other isotopes linked by known Q-values.
Production of ionic and atomic beams of alkaline elements
Abstract An on-line mass spectrometer has been developed and used to perform atomic and nuclear spectroscopy on long series of alkali isotopes including nuclei far from stability. The apparatus was on-line either to the ISOLDE mass separator or directly to the PS, proton beam. In the case of atomic spectroscopy, a thermal atomic beam is needed. As ISOLDE delivers 60 keV ions, a high efficiency “ion-to-atom coverter” has been developed. In all cases, an “ionizer” is required to produce 10 keV ions for the ion source of the mass spectrometer. These two special devices are described, their efficiency and the consequent delay times discussed. The different targets which have been developed for …