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arXiv · 2407.17668

Resonances and collisional properties of neutron-rich helium isotopes in the adiabatic hyperspherical representation

Michael D. Higgins·Chris H. Greene
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Abstract

This work treats few-body systems consisting of neutrons interacting with a $^{4}{\mathrm{He}}$ nucleus. The adiabatic hyperspherical representation is utilized to solve the $N$-body Schr$\ddot{\mathrm{o}}$dinger equation for the three- and four-body systems, treating both $^{6}{\mathrm{He}}$ and $^{7}{\mathrm{He}}$ nuclei. A simplified central potential model for the $^{4}{\mathrm{He}}-n$ interaction is used in conjunction with a spin-dependent three-body interaction to reproduce $^{6}{\mathrm{He}}$ bound-state and resonance properties as well as properties for the $^{8}{\mathrm{He}}$ nucleus in its ground-state. With this Hamiltonian, the adiabatic hyperspherical representation is used to compute bound and scattering states for both $^{6}{\mathrm{He}}$ and $^{7}{\mathrm{He}}$ nuclei. For the $^{6}{\mathrm{He}}$ system, the electric quadrupole transition between the $0^{+}$ and $2^{+}$ state is investigated. For the $^{7}{\mathrm{He}}$ system, $^{6}{\mathrm{He}}+n$ elastic scattering is investigated along with the four-body recombination process $^{4}{\mathrm{He}}+n+n+n\rightarrow$$^{6}{\mathrm{He}}+n$ and breakup process $^{6}{\mathrm{He}}+n\rightarrow$$^{4}{\mathrm{He}}+n+n+n$.

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Michael D. Higgins, Chris H. Greene. 2024-07-24. Resonances and collisional properties of neutron-rich helium isotopes in the adiabatic hyperspherical representation. https://doi.org/10.1103/physrevc.111.014001

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