Abstract
The electromagnetic properties of low-lying states in 70Ge were investigated via multistep Coulomb excitation of a 70Ge beam impinging on a 208Pb target at the ATLAS facility of the Argonne National Laboratory. A total of 27 transitional elements and six diagonal matrix elements coupling 11 low-lying states were extracted from the measured cross sections. These were used to calculate reduced transition probabilities, spectroscopic quadrupole moments, and rotational invariant shape parameters, providing enhanced precision and expanding on previous studies. The experimental data were compared within several theoretical frameworks, including the generalized triaxial rotor model, configuration-interaction shell-model calculations, and computations within the combined frameworks of relativistic density functional theory and the five-dimensional collective Hamiltonian. The results demonstrate a good agreement with the experimental data and, in conjunction with calculations using a two-state mixing model, support significant triaxiality and strong mixing between the 0+1and 0+2 states. This results in the magnitudes of their respective quadrupole deformations [βrms(+1 ) = 0.228 (3), βrms(0+2 ) = 0.273 (1)] being more similar than previously observed. The implications of these results for understanding the complex shape coexistence phenomena, the role of triaxiality, and shape evolution along the Ge isotopic chain are discussed.
| Original language | English |
|---|---|
| Pages (from-to) | 343321-3433213 |
| Number of pages | 3089893 |
| Journal | Physical Review C |
| Volume | 112 |
| Issue number | 3 |
| DOIs | |
| State | Published - Sep 25 2025 |
Funding
This work was supported in part by the U.S. Department of Energy (DOE), Office of Science, Office of Nuclear Physics, under Grants No. DE-SC0023010 [The University of North Carolina at Chapel Hill (UNC)], No. DE-FG02-97ER41041 (UNC), No. DE-FG02-97ER41033 (Triangle Universities Nuclear Laboratory, Duke University), No. DE-AC02-06CH11357 (ANL), No. DE-AC02-05CH11231 [Lawrence Berkeley National Laboratory (LBNL)], No. DE-AC52-07NA27344 (Lawrence Livermore National Laboratory), No. DE-FG02-94ER40834, No. DE-FG02-08ER41556, No. DE-FG02-94ER40848, and No. DE-SC0020451; the NSF under Contracts No. PHY-0606007, No. PHY-2011890, No. PHY-2208137, and No. PHY-2310059; the UNC Startup Funds of A. D. Ayangeakaa; the National Natural Science Foundation of China under Grant No. 12205103; and the National Key Research and Development Program of China under Grants No. 2024YFE0109800 and No. 2024YFE0109803. Work at Los Alamos National Laboratory, operated by Triad National Security, LLC, for the National Nuclear Security Administration of the U.S. Department of Energy, was done under Contract No. 89233218CNA000001. GRETINA was funded by the U.S. DOE, Office of Science, Office of Nuclear Physics, and operated by the ANL and LBNL contract numbers above. This research used the resources of Argonne National Laboratory’s ATLAS facility, a DOE Office of Science User Facility.