Ab initio multi-shell valence-space Hamiltonians and the island of inversion

Abstract

In the shell-model framework, valence-space Hamiltonians connecting multiple major-oscillator shells are of key interest for investigating the physics of neutron-rich nuclei, which have been the subject of intense experimental activity for decades. Here we present an extension of the ab initio valence-space in-medium similarity renormalization group which allows the derivation of such Hamiltonians nonperturbatively. Starting from initial two- and three-nucleon forces from chiral effective field theory, we then calculate properties of nuclei in the important island-of-inversion region above oxygen, so far unexplored with ab initio methods. Our results in the neon and magnesium isotopes indicate the importance of neutron excitation from the $sd$ to $pf$ shells and ground states dominated by intruder configurations around $N=20$, consistent with the conclusions from phenomenological studies. We also benchmark the excitation spectrum of ${}^{16}$O with coupled-cluster theory, finding generally good agreement, and discuss implications for ground state energies and charge radii in oxygen and calcium isotopes. Finally we outline the proper procedure for treating the long-standing issue of center-of-mass contamination, and show that with a particular choice of valence space, these spurious states can be removed successfully.

11 pages, 9 figures, published version

References in corpus (17)

• Chiral effective field theory and nuclear forces
• Improved nuclear matter calculations from chiral low-momentum interactions
• Accurate nuclear radii and binding energies from a chiral interaction
• Thick-Restart Block Lanczos Method for Large-Scale Shell-Model Calculations
• Discrepancy between experimental and theoretical $\beta$-decay rates resolved from first principles
• A nucleus-dependent valence-space approach to nuclear structure
• In-Medium Similarity Renormalization Group for Nuclei
• Non-Empirical Interactions for the Nuclear Shell Model: An Update
• In-Medium Similarity Renormalization Group with Chiral Two- Plus Three-Nucleon Interactions
• ${}^{78}$Ni revealed as a doubly magic stronghold against nuclear deformation
• In-Medium Similarity Renormalization Group for Open-Shell Nuclei
• Discovery of the shape coexisting 0+ state in 32Mg by a two neutron transfer reaction
• Ab Initio Multi-Reference In-Medium Similarity Renormalization Group Calculations of Even Calcium and Nickel Isotopes
• Quantified limits of the nuclear landscape
• In-Medium Similarity Renormalization Group for Closed and Open-Shell Nuclei
• Ab-initio computation of neutron-rich oxygen isotopes
• Neutrinoless double-beta decay matrix elements in large shell-model spaces with the generator-coordinate method

Cited by in corpus (59)

• A Guided Tour of Ab Initio Nuclear Many-Body Theory
• Converged ab initio calculations of heavy nuclei
• Opportunities for Fundamental Physics Research with Radioactive Molecules
• Nuclear Charge Radii of the Nickel Isotopes ${}^{58-68,70}$Ni
• Angular-momentum projection in coupled-cluster theory: structure of ${}^{34}$Mg
• What is ab initio in nuclear theory?
• Mass measurements of 99-101In challenge ab initio nuclear theory of the nuclide 100Sn
• Combining the in-medium similarity renormalization group with the density matrix renormalization group: Shell structure and information entropy
• Accessing ground state and excited states energies in many-body system after symmetry restoration using quantum computers
• Shape coexistence in even-even nuclei: A theoretical overview
• Impact of two-body currents on magnetic dipole moments of nuclei
• Nuclear charge radii of silicon isotopes
• High-resolution laser spectroscopy of ${}^{27-32}$Al
• Nuclear spin-dependent parity-violating effects in light polyatomic molecules
• Multiscale physics of atomic nuclei from first principles
• Ab initio structure factors for spin-dependent dark matter direct detection
• Electromagnetic Properties of Indium Isotopes Elucidate the Doubly Magic Character of ${}^{100}$Sn
• Microsecond Isomer at the N=20 Island of Shape Inversion Observed at FRIB
• Improved structure of calcium isotopes from ab initio calculations
• Surprising charge-radius kink in the Sc isotopes at N=20
• Ab initio computations of strongly deformed nuclei around ${}^{80}$Zr
• Deformed in-medium similarity renormalization group
• Summit of the N=40 Island of Inversion: precision mass measurements and ab initio calculations of neutron-rich chromium isotopes
• High-precision mass measurements of neutron deficient silver isotopes probe the robustness of the $N$ = 50 shell closure
• Nuclear charge radii of Na isotopes: A tale of two theories
• ${}^{40}$Ca transverse response function from coupled-cluster theory
• Ab initio calculation of muon capture on ${}^{24}$Mg
• Mapping the $N=40$ Island of Inversion: Precision Mass Measurements of Neutron-rich Fe Isotopes
• Isomeric excitation energy for ${}^{99}$In${}^m$ from mass spectrometry reveals constant trend next to doubly magic ${}^{100}$Sn
• $\mathbf{N}=32$ shell closure below calcium: Low-lying structure of ${}^{50}$Ar
• Moments and Radii of exotic Na and Mg isotopes
• Density matrix renormalization group description of the island of inversion isotopes ${}^{28-33}$F
• Role of quadrupole deformation and continuum effects in the "island of inversion'' nuclei ${}^{28,29,31}$F
• Effective shell-model interaction for nuclei southeast of ${}^{100}$Sn
• Proton-neutron pairing correlations in the self-conjugate nucleus ${}^{42}$Sc
• Electromagnetic moments of the antimony isotopes ${}^{112-133}$Sb
• Spectroscopy of ${}^{33}$Mg with knockout reactions
• Study of structure and radii for ${}^{20-31}$Na isotopes using microscopic interactions
• 16O electroweak response functions from first principles
• Optimized nuclear energy density functionals including long-range pion contributions
• Single-particle and collective structures in neutron-rich Sr isotopes
• Ab initio nuclear shape coexistence and emergence of island of inversion around $N=20$
• Ground State Magnetic Dipole Moment of ${}^{40}$Sc
• Refined topology of the N = 20 island of inversion with high precision mass measurements of ${}^{31-33}$Na and ${}^{31-35}$Mg
• In-beam $\gamma$-ray spectroscopy of ${}^{32}$Mg via direct reactions
• Structure of odd-mass Ne, Na, and Mg nuclei
• Spectroscopy of deeply bound orbitals in neutron-rich Ca isotopes
• How do mirror charge radii constrain density dependence of the symmetry energy?
• Ab initio study of island of inversion in odd-$A$ nuclei: Structure of ${}^{31,33}$Mg
• Cross-shell excited configurations in the structure of 34Si
• Ab initio calculations of monopole sum rules: From finite nuclei to infinite nuclear matter
• Evolution of shell structure at $\mathbf{N}=32$ and 34: Insights from realistic nuclear forces
• Reduction in nuclear size and quadrupole deformation of high-spin isomers of 127,129In
• Ab initio calculations of beta-decay half-lives for $N=50$ neutron-rich nuclei
• Isoscalar, isovector and orbital contributions in $M1$ transitions from analogous $M1$ and Gamow-Teller transitions in $T=\frac{1}{2}$ mirror nuclei
• Ab initio study in the island of inversion within the two-major-shell valence space
• Towards shell model interactions with credible uncertainties
• Ab initio short-range nuclear matrix elements for neutrinoless double-beta decay
• Ab initio study of $\beta$-decay and pairing in $N=Z$ nuclei