Direct observation of three-neutron emission from ${}^7$He${}^{\ast }$ and the search for the trineutron

S. W. Huang, C. Lenain, Z. H. Yang +107

Three-neutron emission from ${}^7$He has been directly measured for the first time, following neutron knockout from a ${}^8$He beam at 156 MeV/nucleon. A resonance-like structure at $2…