Absence of Low-Energy Shape Coexistence in $^{80}$Ge: The Nonobservation of a Proposed Excited 0$_2^+$ Level at 639 keV

The Ge-80 structure was investigated in a high-statistics beta-decay experiment of Ga-80 using the GRIFFIN spectrometer at TRIUMF-ISAC through gamma, beta-e, e-gamma, and gamma-gamma spectroscopy. No evidence was found for the recently reported 0(2)(+) 639-keV level suggested as evidence for low-energy shape coexistence in Ge-80. Large- scale Ge-78(,)80(,)82 shell model calculations performed in place the 0(2)(+) level in Ge-80 at 2 MeV. The new experimental evidence combined with shell model predictions indicate that low-energy shape coexistence is not present in Ge-80.