Based on experimental evidence from the Sm144(α,2n) reaction, the 3484.7-keV 6+ state in Gd146 is identified as the highest-spin member of the 3--3- two-phonon octupole quartet. A previously unknown γ line of 1905.8 keV and E3 character feeding the 3- octupole state has been observed. These results represent the first observation of a 6+→3-→0+ cascade of two E3 transitions in an even-even nucleus and provide strong support for the interpretation of the 6+ state as a two-phonon octupole excitation.
ASJC Scopus subject areas
- Nuclear and High Energy Physics