@Article{Ciemala_etal2020, author="Ciemala, M. et al and Domingo-Pardo, C. and Perez-Vidal, R. M.", title="Testing ab initio nuclear structure in neutron-rich nuclei: Lifetime measurements of second 2(+) state in C-16 and O-20", journal="Physical Review C", year="2020", publisher="Amer Physical Soc", volume="101", number="2", pages="021303--7pp", abstract="To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2(+) state in neutron-rich O-20, tau(2(2)(+)) = 150(-30)(+80) fs, and an estimate for the lifetime of the second 2(+) state in C-16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted gamma-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O-18 (7.0 MeV/u) + Ta-181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced gamma-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O-20 and with the no-core shell model for C-16. The present measurement shows the power of electromagnetic observables, determined with high-precision gamma spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available.", optnote="WOS:000517222700001", optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=4311), last updated on Wed, 18 Mar 2020 17:52:33 +0000", issn="2469-9985", doi="10.1103/PhysRevC.101.021303", opturl="https://arxiv.org/abs/2002.04814", opturl="https://doi.org/10.1103/PhysRevC.101.021303", language="English" }