Modeling the double charge exchange response function for a tetraneutron system

This work is an attempt to model the 4n response function of a recent RIKEN experimental study of the double charge exchange 4He(⁠ 8He, 8Be) 4n reaction in order to put in evidence an eventual enhancement mechanism of the zero-energy cross section, including a near-threshold resonance. This resonance can indeed be reproduced only by adding to the standard nuclear Hamiltonian an unphysically large T=3/2 attractive 3n-force that destroys the neighboring nuclear chart. No other mechanisms, like cusps or related structures, were found.