4He(stopped K−, n) spectroscopy for deeply bound kaonic nuclear states

A feasibility study has been made on a new type of nuclear spectroscopy—namely the (stopped K−, n) reaction, to search for nuclear K̄ bound states. Particular attention was focussed on the process 4He(stopped K−, n) to form a deeply bound K̄ state in 3He, which is predicted to be a narrow discrete state with a binding energy of 108 MeV and a width of 20 MeV. A monoenergetic neutron peak resulting from this reaction is expected to be seen on a continuous background arising from the successive reactions and decays produced in K− absorption by 4He.