Article

Discovery of Rn-229 and the Structure of the Heaviest Rn and Ra Isotopes from Penning-Trap Mass Measurements

Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
Physical Review Letters (Impact Factor: 7.73). 04/2009; 102(11):112501. DOI: 10.1103/PhysRevLett.102.112501
Source: PubMed

ABSTRACT The masses of the neutron-rich radon isotopes {223-229}Rn have been determined for the first time, using the ISOLTRAP setup at CERN ISOLDE. In addition, this experiment marks the first discovery of a new nuclide, 229Rn, by Penning-trap mass measurement. The new, high-accuracy data allow a fine examination of the mass surface, via the valence-nucleon interaction deltaV{pn}. The results reveal intriguing behavior, possibly reflecting either a N=134 subshell closure or an octupolar deformation in this region.

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