Pauli-principle driven correlations in four-neutron nuclear decays

Abstract

Mechanism of simultaneous non-sequential four-neutron (4n) emission (or "true" 4n-decay) has been considered in phenomenological five-body approach. This approach is analogous to the model of the direct decay to the continuum often applied to 2n-and 2p-decays. It is demonstrated that 4n-decay fragments should have specific energy and angular correlations reflecting strong spatial correlations of "valence" nucleons orbiting in their 4n-precursors. Due to the Pauli exclusion principle, the valence neutrons are pushed to the symmetryallowed configurations in the 4n-precursor structure, which causes a "Pauli focusing" effect. Prospects of the observation of the Pauli focusing have been considered for the 4n-precursors 7 H and 28 O. Fingerprints of their nuclear structure or/and decay dynamics are predicted.