Document Type
Article
Department/Program
Physics
Journal Title
Physical Review Letters
Pub Date
2015
Volume
115
Issue
4
Abstract
We have measured the hyperfine splitting of the 7P(1/2) state at the 100 ppm level in Fr isotopes (Fr-206g,Fr-206m,Fr-207,Fr-209,Fr-213,Fr-221) near the closed neutron shell (N = 126 in Fr-213). The measurements in five isotopes and a nuclear isomeric state of francium, combined with previous determinations of the 7S(1/2) splittings, reveal the spatial distribution of the nuclear magnetization, i.e., the Bohr-Weisskopf effect. We compare our results with a simple shell model consisting of unpaired single valence nucleons orbiting a spherical nucleus, and find good agreement over a range of neutron-deficient isotopes (Fr207-213). Also, we find near-constant proton anomalies for several even-N isotopes. This identifies a set of Fr isotopes whose nuclear structure can be understood well enough for the extraction of weak interaction parameters from parity nonconservation studies.
Recommended Citation
Zhang, J., Tandecki, M., Collister, R., Aubin, S., Behr, J. A., Gomez, E., ... & FrPNC Collaboration. (2015). Hyperfine anomalies in Fr: boundaries of the spherical single particle model. Physical review letters, 115(4), 042501.
DOI
10.1103/PhysRevLett.115.042501
