How Robust is the N = 34 Subshell Closure? First Spectroscopy of ${}^{52}$Ar

Abstract

The first $\gamma$-ray spectroscopy of ${}^{52}$Ar, with the neutron number N = 34, was measured using the ${}^{53}$K(p,2p) one-proton removal reaction at $\sim$210 MeV/u at the RIBF facility. The 2${}_1^{+}$ excitation energy is found at 1656(18) keV, the highest among the Ar isotopes with N $>$ 20. This result is the first experimental signature of the persistence of the N = 34 subshell closure beyond ${}^{54}$Ca, i.e., below the magic proton number Z = 20. Shell-model calculations with phenomenological and chiral-effective-field-theory interactions both reproduce the measured 2${}_1^{+}$ systematics of neutron-rich Ar isotopes, and support a N = 34 subshell closure in ${}^{52}$Ar.

References in corpus (32)

• Modern Theory of Nuclear Forces
• Chiral effective field theory and nuclear forces
• Nuclear magic numbers: new features far from stability
• Improved nuclear matter calculations from chiral low-momentum interactions
• Novel features of nuclear forces and shell evolution in exotic nuclei
• Coupled-cluster computations of atomic nuclei
• Accurate nuclear radii and binding energies from a chiral interaction
• The In-Medium Similarity Renormalization Group: A Novel Ab Initio Method for Nuclei
• Unexpectedly large charge radii of neutron-rich calcium isotopes
• Collapse of the N=28 shell closure in ${}^{42}$Si
• A nucleus-dependent valence-space approach to nuclear structure
• Evolution of shell structure in neutron-rich calcium isotopes
• Identification and Separation of Radioactive Isotope Beams by the BigRIPS Separator at the RIKEN RI Beam Factory
• Shape transitions in exotic Si and S isotopes and tensor-force-driven Jahn-Teller effect
• Saturation with chiral interactions and consequences for finite nuclei
• A new effective interaction for $0\hslash \omega$ shell model calculations in the sdpf valence space
• DALI2: A NaI(Tl) detector array for measurements of $\gamma$ rays from fast nuclei
• In-Medium Similarity Renormalization Group for Open-Shell Nuclei
• Three-body monopole corrections to the realistic interactions
• Probing the N = 32 shell closure below the magic proton number Z = 20: Mass measurements of the exotic isotopes 52,53K
• Ground and excited states of doubly open-shell nuclei from ab initio valence-space Hamiltonians
• Dawning of the N=32 shell closure seen through precision mass measurements of neutron-rich titanium isotopes
• The N = 16 spherical shell closure in 24O
• Exploring sd-shell nuclei from two- and three-nucleon interactions with realistic saturation properties
• Quasi-free (p,2p) and (p,pn) reactions with unstable nuclei
• Pauli blocking and medium effects in nucleon knockout reactions
• Non-observable nature of the nuclear shell structure. Meaning, illustrations and consequences
• Ab initio coupled-cluster theory for open-shell nuclei
• Spins and Magnetic Moments of ${}^{49}$K and ${}^{51}$K: establishing the 1/2${}^{+}$ and 3/2${}^{+}$ level ordering beyond $N$ = 28
• Direct mass measurements of neutron-rich ${}^{86}$Kr projectile fragments and the persistence of neutron magic number $N$ = 32 in Sc isotopes
• Structure of 55Sc and development of the N=34 subshell closure
• Spectroscopy of 46Ar by the (t,p) two-neutron transfer reaction

Cited by in corpus (33)

• A Guided Tour of Ab Initio Nuclear Many-Body Theory
• Global sensitivity analysis of bulk properties of an atomic nucleus
• Coupled-cluster calculations of neutrinoless double-beta decay in ${}^{48}$Ca
• Coherent elastic neutrino-nucleus scattering on 40Ar from first principles
• Ab initio computation of the longitudinal response function in ${}^{40}$Ca
• Shell evolution of $N=40$ isotones towards ${}^{60}$Ca: First spectroscopy of ${}^{62}$Ti
• Precision mass measurements of neutron-rich scandium isotopes refine the evolution of $N=32$ and $N=34$ shell closures
• Moving away from singly-magic nuclei with Gorkov Green's function theory
• New magicity $N=32$ and $34$ triggered by strong couplings between Dirac inversion partners
• Emergence of simple patterns in many-body systems: from macroscopic objects to the atomic nucleus
• Improved structure of calcium isotopes from ab initio calculations
• Examining the $N$ = 28 shell closure through high-precision mass measurements of ${}^{46-48}$Ar
• Shell-model based study of the direct capture in neutron-rich nuclei
• $\mathbf{N}=32$ shell closure below calcium: Low-lying structure of ${}^{50}$Ar
• Improved description of nuclear charge radii: Global trends beyond $N=28$ shell closure
• Direct probing of the cluster structure in ${}^{12}$Be via $\alpha$-knockout reaction
• Shell-model study of titanium isotopic chain with chiral two- and three-body forces
• Investigation of the ground-state spin inversion in the neutron-rich 47,49Cl isotopes
• Structure of ${}^{46,47}$Ca from the ${\beta }^{-}$ decay of ${}^{46,47}$K in the framework of nuclear shell model
• Potential signature of new magicity from universal aspects of nuclear charge radii
• Global Framework for Emulation of Nuclear Calculations
• Universal Effective Charges in the $sd$ and $fp$ Shells
• Nuclear structure and direct reaction studies in particle-$\gamma$ coincidence experiments at the FSU John D. Fox Superconducting Linear Accelerator Laboratory
• On the robustness of sub-shell closures: A high angular momentum analysis of the titanium isotopes
• Ab initio models of atomic nuclei: challenges and new ideas
• Spectroscopy of ${}^{52}$K
• Evolution of shell structure at $\mathbf{N}=32$ and 34: Insights from realistic nuclear forces
• A way forward towards improvement of tensor force in \textit{pf}-shell
• Estimate of the location of the neutron drip line for calcium isotopes from an exact Hamiltonian with continuum pair correlations
• Bridging reaction theory and nuclear structure in ${\pi }^{\pm }$-${}^{48}$Ca scattering
• Systematic analysis of the nuclear absorption effect on the cross section of the knockout reaction
• Neutron skins probed in proton knockout from neutron-rich nuclei
• Experimental study of ${}^{53}$Cr via the $(d,p\gamma )$ reaction