Neutron decay spectroscopy has become a successful tool to explore nuclear properties of nuclei with the largest neutron-to-proton ratios. Resonances in nuclei located beyond the neutron dripline are accessible by kinematic reconstruction of the decay products. The development of two-neutron detection capabilities of the Modular Neutron Array (MoNA) at NSCL has opened up the possibility to search for unbound nuclei which decay by the emission of two neutrons. Specifically, this exotic decay mode was observed in16Be and 26O.
Thoennessen, M, Z Kholey, A Spyrou, E Lunderberg, Paul A. DeYoung, H Attanayake, T Baumann, D Bazin, B A. Brown, G Christian, D Divaratne, S M. Grimes, A Haagsma, J E. Finck, N Frank, B Luther, S Mosby, T Nagi, Graham F. Peaslee, W A. Peters, A Schiller, J K. Smith, J Snyder, M Strongman and A Volya. "Observation of Ground-State Two-Neutron Decay." Acta Physica Polonica B 44, no. 3 (2013). http://dx.doi.org/10.5506/APhysPolB.44.543