Resonance State In H-7

The existence of the H-7 nuclear system was investigated via a one-proton transfer reaction with a He-8 beam at 15.4A MeV and a C-12 gas target. The experimental setup was based on the active-target MAYA which allowed a complete reconstruction of the reaction kinematics. The existence of the H-7 was confirmed with the identification of seven events where the system was formed with a resonance energy of 0.57(-0.21)(+0.42) MeV above the H-3+4n threshold and a resonance width of 0.09(-0.06)(+0.94) MeV. This study represents an unambiguous proof of the existence of the most neutron-proton unbalanced system presently found.