Jaume Carbonell, Emiko Hiyama, Rimantas Lazauskas, F. Miguel Marqués
SciPost Phys. Proc. 3, 008 (2020) ·
published 24 February 2020

· pdf
We consider the evolution of the neutronnucleus scattering length
for the lightest nuclei. We show that, when increasing the number of neutrons in the target nucleus, the strong Pauli repulsion is weakened
and the balance with the attractive nucleonnucleon interaction results into a resonant virtual state in $^{18}$B.
We describe $^{19}$B in terms of a $^{17}$B$n$$n$ threebody system where the twobody subsystems $^{17}$B$n$
and $n$$n$ are unbound (virtual) states close to the unitary limit. The energy of $^{19}$B ground state is
well reproduced and two lowlying resonances are predicted.
Their eventual link with the Efimov physics is discussed.
This model can be extended to describe the recently discovered resonant states in $^{20,21}$B.
Prof. Carbonell: "Many thanks for your very usef..."
in Report on Lowenergy neutron scattering on light nuclei and 19B as a 17Bnn threebody system in the unitary limit