T. Möller

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

Low-energy quadrupole-collective excitations of isovector character, the so-called states with proton-neutron mixed-symmetric character (MSS), have been investigated in 204Hg which is the sole stable nucleus in the straight vicinity of 208Pb exhibiting a 2π — 2ν structure. A 12C(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 of 204Hg 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 of 204Hg.

Exotic ideas on mixed proton-neutron symmetry and their manifestation in heavy nuclei

The one-quadrupole phonon excitation of mixed symmetry, the 2+1,ms state, is a fundamental building block of nuclear structure. This article gives a summary of our recent experimental research on this excitation mode in the A = 90 and A = 130 mass regions.

Projectile Coulomb Excitation of the nucleus 194Pt

Low-lying collective excited states of 194Pt have been studied via the 12C(194Pt,194Pt*) projectile Coulomb excitation reaction at 85% of the Coulomb barrier (850 MeV) using the Gammasphere Ge-detector array at Argonne National Laboratory. Absolute E2 transition strengths have been obtained from the Coulex cross sections that were deduced from the relative γ-ray yields. They are discussed with respect to the structure suggested by the O(6) symmetry of the Interacting Boson Model.

The beauty of good data: Unveiling the traces of mixed symmetry

The one-quadrupole phonon excitation of mixed symmetry, the 2+1,ms state, is a fundamental building block of nuclear structure. This article gives a summary of our recent experimental research on this excitation mode in the A = 90 and A = 130 mass regions.