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arXiv · 2602.01989

Is $^{40}$Mg a Borromean halo nucleus? A case built on the electric-dipole response

Jagjit Singh·J. Casal·N. R. Walet·W. Horiuchi·W. Satuła
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Abstract

We investigate the low-energy electric-dipole response of $^{40}$Mg using a $^{38}$Mg$+n+n$ three-body model. This model is implemented using a three-body hyperspherical formalism with an analytical transformed harmonic oscillator basis. In this study, two different neutron-neutron interactions are considered: a scalar Gaussian density-dependent central potential and a more realistic finite-range potential which includes central, spin-orbit, and tensor components. We examine how electric-dipole response is affected by the choice of the interaction.

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Jagjit Singh, J. Casal, N. R. Walet, W. Horiuchi, W. Satuła. 2026-02-02. Is $^{40}$Mg a Borromean halo nucleus? A case built on the electric-dipole response. https://arxiv.org/abs/2602.01989

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