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Title	Measurement of ground state properties of neutron-rich nuclei on the r-process path between the N=50 and N=82 shells
Author(s)	Barton, C J
Experiment	IS458
Greybook	See IS458 experiment
Approved	10 September 2007
Status	Finished
Collaboration	ISOLDE
Accelerator	CERN ISOLDE
Abstract	The evolution of the unknown ground-state ${\beta}$-decay properties of the neutron-rich $^{84-89}$Ge, $^{90-93}$Se and $^{102-104}$Sr isotopes near the r-process path is of high interest for the study of the abundance peaks around the N=50 and N=82 neutron shells. At ISOLDE, beams of certain elements with sufficient isotopic purity are produced as molecular sidebands rather than atomic beams. This applies e.g, to germanium, separated as GeS$^{+}$, selenium separated as SeCO$^{+}$ and strontium separated as SrF$^{+}$. However, in case of neutron-rich isotopes produced in actinide targets, new "isobaric" background of atomic ions appears on the mass of the molecular sideband. For this particular case, the ECR charge breeder, positioned in the experimental hall after ISOLDE first mass separation, can be advantageously used as a purification device, by breaking the molecules and removing the molecular contaminants. This proposal indicates our interest in the study of basic nuclear structure properties of neutron-rich nuclei on the r-process path between the neutron magic numbers N=50 and N=82 at ISOLDE with the ECR Phoenix Booster. This first proposal should serve as a basis for the investigation of the potential applications of the ECR for nuclear astrophysics at ISOLDE. For instance, beam purification using molecular sidebands selection with the ECR is particularly suited for the study of the $^{84-89}$Ge, $^{90-93}$Se, $^{102-104}$Sr isotopes, respectively produced as GeS$^{+}$, SeCO$^{+}$ and SrF$^{+}$ molecular beams.
Related document(s)	CERN-INTC-2007-012  (INTC-P-225)

Contact: Delahaye, P
Contact: Cederkall, A J