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arXiv · 1806.02936

Energy Spectrum of Neutron-Rich Helium Isotopes: Complex Made Simple

K. Fossez·J. Rotureau·W. Nazarewicz
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Abstract

We demonstrate that the intricate energy spectrum of neutron-rich helium isotopes can be straightforwardly described by taking advantage of the low-energy properties of neutron-neutron interaction and the scale separation that is present in diluted dripline systems. By using arguments based on the halo effective field theory, we carry out a parameter reduction of the complex-energy configuration interaction framework in the $spd$ space, including resonant and scattering states. By adjusting only one parameter, the strength of the spin-singlet central neutron-neutron interaction, we reproduce experimental energies and widths of $^{5-8}$He within tens of keV precision. We predict a parity inversion of narrow resonances in $^{9}$He and show that the ground state of $^{10}$He is an $s$-wave-dominated threshold configuration that could decay through two-neutron emission.

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K. Fossez, J. Rotureau, W. Nazarewicz. 2018-06-08. Energy Spectrum of Neutron-Rich Helium Isotopes: Complex Made Simple. https://doi.org/10.1103/physrevc.98.061302

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