beta decay of Ar-49,Ar-50

Artikel i vetenskaplig tidskrift, 2003

Information on gross beta-decay properties of neutron-rich noble gas isotopes Ar-49,Ar-50 was obtained at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma ion source with a cooled transfer line and subsequent mass separation. A doubly charged beam was used in the case of Ar-49 to suppress the corresponding multicharged background from heavier noble gas fission products. The comparison of the obtained data with results of quasiparticle random-phase approximation calculations indicates that the N=28 shell is not disturbed significantly for neutron-rich Ar nuclei. The obtained results are useful for better understanding of the origin of the Ca-48/Ca-46 isotopic anomaly discovered in inclusions from the Allende meteorite.