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Title	Precision mass measurements with ISOLTRAP to study the evolution of the $\textit{N}$=82 shell gap far from stability
Author(s)	Manea, V
Experiment	IS574
Greybook	See IS574 experiment
Approved	27 November 2013
Status	Completed on 30 April 2020
Collaboration	ISOLDE
Accelerator	CERN ISOLDE
Abstract	Shell effects and their evolution across the nuclear chart impose important constraints on the modelling of the nucleon-nucleon interaction. The strength of shell closures in neutron-rich nuclei also influences the path of the $\textit{r}$-process of nucleo-synthesis and the predicted elemental abundances. We propose to measure the masses of the isotopes $^{132,133}$In, $^{129-132}$Cd, $^{125-129}$Ag with the Penning-trap mass spectrometer ISOLTRAP. The recently developed multi-reflection time-of-flight mass separator of ISOLTRAP will allow, as a beam purifier, to handle higher contamination ratios than before and, for the more exotic cases, to directly determine the mass of the nuclides of interest. The masses of the proposed isotopes will allow the investigation of a possible weakening of the $\textit{N}$ = 82 shell gap for $\textit{Z}$ < 50 and corresponding $\textit{r}$-process waiting point. This in turn enables an exploration of the impact on the $\textit{A}$ = 130 $\textit{r}$-process abundances.
Related document(s)	CERN-INTC-2013-022  (INTC-P-382)

Contact: Manea, V