Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2610.05648

$^{86}$Ni: Possible doubly-magic nucleus with neutron halo

H. Nakada·K. Ishida
View original source ↗Read source document ↗Export metadata ↓

Abstract

Self-consistent mean-field calculations with semi-realistic interactions have predicted that $N=58$ becomes a magic number near Ni, where the $n2s_{1/2}$ orbit is the highest occupied state. As the last neutrons occupy the shallowly bound $s$-orbit, $^{86}$Ni can be highly distinctive, being a doubly-magic nucleus and possessing a neutron halo simultaneously. With minimal ambiguity in the many-body wave function, it may provide a unique opportunity to investigate, \textit{e.g.}, reaction mechanisms in halo nuclei. As an example, we present differential cross sections for proton elastic scattering predicted via a folding potential without local approximations, and compare them with those obtained using an empirical potential.

Explore related subjects

nucl-th

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

H. Nakada, K. Ishida. 2026-10-05. $^{86}$Ni: Possible doubly-magic nucleus with neutron halo. https://arxiv.org/abs/2610.05648

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Generalized U(N) gauge transformations in the realm of the extended covariant Hamilton formalism of field theory

The Lagrangians and Hamiltonians of classical field theory require compensating gauge fields in order to realize local internal gauge invariance with the standard transformation laws. This principle is developed in the extended covariant canonical transformation formalism, which also accommodates changes of spacetime coordinates. The construction yields locally U$(N)$-invariant matter--gauge-field actions and, in a separate application, diffeomorphism-covariant actions for ordinary vector fields and an independent affine connection. The latter application adopts a covariant-derivative coupling prescription whose antisymmetric vector-momentum sector contains a direct interaction with torsion. This interaction is not required by diffeomorphism covariance alone and does not apply to the internal gauge connection with its standard inhomogeneous transformation law. The compensating terms are distinguished from additional invariant interactions and from the gravitational dynamics, which must be specified independently.

nucl-th↗
arXiv2026

Nucleon electromagnetic form-factors in a minimal Gari-Krümpelmann model including two-meson continua

The Gari--Krümpelmann (GK) model provided one of the first semiphenomenological descriptions of the electromagnetic nucleon form-factors over a wide range of momentum transfer. It combined vector-meson dominance at low and intermediate momentum transfer with perturbative-QCD constraints at large momentum transfer. The present work extends this framework by including the dispersive two-pion continuum explicitly in the isovector channel. The two-pion contribution is taken from modern dispersive analyses and embedded into the intrinsic high-$Q^2$ structure of the GK ansatz. The physical $ρ$ dynamics is then interpreted as part of the correlated two-pion spectral function. Similarly, we include in the isoscalar spectral function the correlated $K\bar K$ and $ρπ$ continua, where the former also includes the $ϕ$-meson pole. The direct coupling terms remain essential for the transition to the asymptotic regime. This gives a cleaner separation between long-range continuum dynamics, coherent vector-meson contributions, and direct quark-current dynamics. With just 7 parameters, we can describe the large body on form-factor data and differential cross sections from electron-proton scattering in the space-like region.

nucl-th↗
arXiv2026

Exact resummation of hydrodynamics for arbitrary elastic scattering integral

We consider monoenergetic particles propagating in three spatial dimensions and undergoing elastic scattering off an external medium. For an arbitrary rotationally invariant scattering kernel, we derive an exact expression for the frequency- and wave-number-dependent diffusivity, thereby resumming the hydrodynamic gradient expansion to all orders. The result is an infinite continued fraction, with each successive level determined by the relaxation rate of a higher angular harmonic of the collision operator. Thus, while ordinary diffusion probes only the first angular harmonic, the resummed constitutive relation retains information about the full scattering kernel. We show how this microscopic information manifests itself in the analytic structure of the diffusivity and in the response to a localized external source. In particular, deviations from Fick's law decay exponentially with distance, at a rate determined by the nearest complex-wavenumber singularity of the inverse diffusivity. Thus, exponentially small departures from hydrodynamics retain detailed information about the underlying scattering process.

nucl-th↗