Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5494849 | Physics Letters B | 2017 | 6 Pages |
Abstract
One-phonon states of vibrational nuclei with mixed proton-neutron symmetry have been observed throughout the nuclear chart besides the mass Aâ200 region. Very recently, it has been proposed that the 22+ state of 212Po is of isovector nature. This nucleus has two valence protons and two valence neutrons outside the doubly-magic 208Pb nucleus. The stable isotope 204Hg, featuring two valence-proton and valence-neutron holes, with respect to 208Pb, is the particle-hole mirror of 212Po. In order to compare the properties of low-lying isovector excitations in these particle-hole mirror nuclei, we have studied 204Hg by using the projectile Coulomb-excitation technique. The measured absolute B(M1;22+â21+) strength of 0.20(2)μN2 indicates that the 22+ level of 204Hg is at least the main fragment of the 21,ms+ state. For the first time in this mass region, both lowest-lying, one-quadrupole phonon excitations are established together with the complete set of their decay strengths. This allows for a microscopic description of their structures, achieved in the framework of the Quasi-particle Phonon Model.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
R. Stegmann, C. Stahl, G. Rainovski, N. Pietralla, C. Stoyanov, M.P. Carpenter, R.V.F. Janssens, M. Lettmann, T. Möller, O. Möller, V. Werner, S. Zhu,