High-precision spectroscopy of ${}^{20}$O benchmarking ab-initio calculations in light nuclei

Abstract

The excited states of unstable ${}^{20}$O were investigated via $\gamma$-ray spectroscopy following the ${}^{19}$O$(d,p{)}^{20}$O reaction at 8 $A$MeV. By exploiting the Doppler Shift Attenuation Method, the lifetime of the 2${}_2^{+}$ and 3${}_1^{+}$ states were firmly established. From the $\gamma$-ray branching and E2/M1 mixing ratios for transitions deexciting the 2${}_2^{+}$ and 3${}_1^{+}$ states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of $\gamma$-ray transition probabilities with the valence space in medium similarity renormalization group ab-initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab-initio approaches using chiral EFT forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab-initio models.

arXiv commentSupplemental Material available

References in corpus (38)

• Improved nuclear matter calculations from chiral low-momentum interactions
• Three-body forces and the limit of oxygen isotopes
• AGATA - Advanced Gamma Tracking Array
• Thick-Restart Block Lanczos Method for Large-Scale Shell-Model Calculations
• Unexpectedly large charge radii of neutron-rich calcium isotopes
• A Guided Tour of Ab Initio Nuclear Many-Body Theory
• Ab initio predictions link the neutron skin of ${}^{208}$Pb to nuclear forces
• Non-Empirical Interactions for the Nuclear Shell Model: An Update
• Ab initio limits of atomic nuclei
• Nuclear forces and their impact on neutron-rich nuclei and neutron-rich matter
• Saturation with chiral interactions and consequences for finite nuclei
• Novel chiral Hamiltonian and observables in light and medium-mass nuclei
• Accurate bulk properties of nuclei from $A=2$ to $\infty$ from potentials with $\Delta$ isobars
• Charge radii of exotic potassium isotopes challenge nuclear theory and the magic character of $N=32$
• Measurement and microscopic description of odd-even staggering of charge radii of exotic copper isotopes
• Quantum Monte Carlo calculations of electromagnetic moments and transitions in A <= 9 nuclei with meson-exchange currents derived from chiral effective field theory
• Converged ab initio calculations of heavy nuclei
• Ab initio electromagnetic observables with the in-medium similarity renormalization group
• Nuclear Charge Radii of the Nickel Isotopes ${}^{58-68,70}$Ni
• Mass measurements of 99-101In challenge ab initio nuclear theory of the nuclide 100Sn
• Ground-State Electromagnetic Moments of Calcium Isotopes
• Systematics of E2 strength in the sd-shell with the valence-space in-medium similarity renormalization group
• Quantum Monte Carlo calculations of magnetic moments and M1 transitions in A<=7 nuclei including meson-exchange currents
• First glimpse of the $N=82$ shell closure below $Z=50$ from masses of neutron-rich cadmium isotopes and isomers
• \texttt{NuHamil}: A numerical code to generate nuclear two- and three-body matrix elements from chiral effective field theory
• Charge radius of the short-lived ${}^{68}$Ni and correlation with the dipole polarizability
• Precision mass measurements of neutron-rich scandium isotopes refine the evolution of $N=32$ and $N=34$ shell closures
• Charge radii of ${}^{55,56}$Ni reveal a surprisingly similar behavior at $N=28$ in Ca and Ni isotopes
• Proton distribution radii of ${}^{16-24}$O: signatures of new shell closures and neutron skin
• Systematics of 2+ states in C isotopes from the ab initio no-core shell model
• Role of chiral two-body currents in ${}^6$Li magnetic properties in light of a new precision measurement with the relative self-absorption technique
• The MUGAST-AGATA-VAMOS campaign : set-up and performance
• Testing ab initio nuclear structure in neutron-rich nuclei: lifetime measurements of second 2+ states in 16C and 20O
• Summit of the N=40 Island of Inversion: precision mass measurements and ab initio calculations of neutron-rich chromium isotopes
• Coulomb excitation of the $\left|T_z\right|=\frac{1}{2}$, $A=23$ mirror pair
• Electromagnetic properties of ${}^{21}$O for benchmarking nuclear Hamiltonians
• Complete set of bound negative-parity states in the neutron-rich 18N nucleus
• Accessing tens-to-hundreds femtoseconds nuclear state lifetimes with low-energy binary heavy-ion reactions

Cited by in corpus (1)

• Angela and the electric dipole response -- giant and pygmy, hot and cold, isoscalar and isovector