Search for the tri- and tetra-neutron in reactions induced by ¹¹B and ⁹Be ions on ⁷Li

Abstract

In three different heavy ion reactions the energy spectra of the ¹⁴O, ¹⁵O and ¹²N nuclei have been measured to obtain some information about their partners in the exit channel - the multineutron systems ⁴n and ³n. No evidence for the existence of any bound state in the multineutron systems has been obtained at the cross section level of 1 nb/MeV · sr achieved in the experiment. The phase-space analysis has given no positive results concerning the existence of quasistationary states in the ⁴n and ³n systems either.