Investigation of the mixed-symmetric one-quadrupole phonon 2+ 1,ms state of the heavy nucleus 204Hg

[摘要] Low-energy quadrupole-collective excitations of isovector character, the so-called states with proton-neutron mixed-symmetric character (MSS), have been investigated in204Hg which is the sole stable nucleus in the straight vicinity of208Pb exhibiting a 2π - 2ν structure. A12C(204Hg,204Hg∗)12C projectile Coulomb-excitation experiment at 890MeV was performed at Argonne National Laboratory using the ATLAS accelerator. γ-rays originating from the decay of the excited states of204Hg were detected using the GAMMASPHERE spectrometer. The measured Coulomb-excitation yields provide the B(M1) and the B(E2) strength distributions which unambiguously reveal the 23+state at 1948 keV as the one-phonon MSS of204Hg.

[发布机构] Institut für Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, Darmstadt; 64289, Germany^1;Faculty of Physics, University of Sofia St. Kliment Ohridski, 5 James Bourchier Blvd., Sofia; 1164, Bulgaria^2;Argonne National Laboratory, 9700 S. Cass Avenue, Argonne; IL; 60439, United States^3

[关键词] Argonne National Laboratory;Collective excitations;Coulomb excitation;Heavy nucleus;Low-energy;Quadrupoles;Stable nuclei;Strength distribution