Testing ab initio nuclear structure in neutron-rich nuclei: lifetime measurements of second 2+ states in 16C and 20O
Creators: name: Ciemala, M.
name: Ziliani, S.
name: Crespi, F. C. L.
name: Leoni, S.
name: Fornal, B.
name: Maj, A.
name: Bednarczyk, P.
name: Benzoni, G.
name: Bracco, A.
name: Boiano, C.
name: Bottoni, S.
name: Brambilla, S.
name: Bast, M.
name: Beckers, M.
name: Braunroth, T.
name: Camera, F.
name: Cieplicka-Orynczak, N.
name: Clement, E.
name: Coelli, S.
name: Dorvaux, O.
name: Erturk, S.
name: de France, G.
name: Fransen, C.
name: Goldkuhle, A.
name: Grebosz, J.
name: Harakeh, M. N.
name: Iskra, L. W.
name: Jacquot, B.
name: Karpov, A.
name: Kicinska-Habior, M.
name: Kim, Y.
name: Kmiecik, M.
name: Lemasson, A.
name: Lenzi, S. M.
name: Lewitowicz, M.
name: Li, H.
name: Matea, I.
name: Mazurek, K.
name: Michelagnoli, C.
name: Matejska-Minda, M.
name: Million, B.
name: Muller-Gatermann, C.
name: Nanal, V.
name: Napiorkowski, P.
name: Napoli, D. R.
name: Palit, R.
name: Rejmund, M.
name: Schmitt, Ch.
name: Stanoiu, M.
name: Stefan, I.
name: Vardaci, E.
name: Wasilewska, B.
name: Wieland, O.
name: Zieblinski, M.
name: Zielinska, M.
name: Atac, A.
name: Barrientos, D.
name: Birkenbach, B.
name: Boston, A. J.
name: Cederwall, B.
name: Charles, L.
name: Collado, J.
name: Cullen, D. M.
name: Desesquelles, P.
name: Domingo-Pardo, C.
name: Dudouet, J.
name: Eberth, J.
name: Gonzalez, V.
name: Goupil, J.
name: Harkness-Brennan, L. J.
name: Hess, H.
name: Judson, D. S.
name: Jungclaus, A.
name: Korten, W.
name: Labiche, M.
name: Lefevre, A.
name: Menegazzo, R.
name: Mengoni, D.
name: Nyberg, J.
name: Perez-Vidal, R. M.
name: Podolyak, Zs.
name: Pullia, A.
name: Recchia, F.
name: Reiter, P.
name: Saillant, F.
name: Salsac, M. D.
name: Sanchis, E.
name: Stezowski, O.
name: Theisen, Ch.
name: Valiente-Dobon, J. J.
name: Holt, J. D.
name: Menendez, J.
name: Schwenk, A.
name: Simonis, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich 20O, tau(2+_2 ) = 150(+80-30) fs, and an estimate for the lifetime of the second 2+ state in 16C 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 femtoseconds range, by analyzing the Doppler-shifted gamma-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction 18O (7.0 MeV/u) + 181Ta. The requested sensitivity could only be reached owing to the excellent performances of the AGATA gamma-tracking array, 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 20O, and with the no-core shell model for 16C. 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 lifetimes measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense ISOL-type beams become available.