Interfering reaction channels observed in the ²H(⁸He,⁴He)⁶H reaction studies

Abstract

In the recent work [Nikolskii et al., Phys. Rev. C 105, 064605 (2022)] the 2H(8He,4He)6H reaction was used for the study of the extreme neutron-rich 6H isotope. A broad bump was observed in the measured 6H spectrum interpreted as the broad overlapping ground and some low-lying states of this nuclide. There could be certain doubts in the interpretation of this work: in conditions of the limited phase space it is not impossible that the structure in the missing mass spectrum of 6H is actually induced by the resonant states populated by some other channels opened in the 8He+2H interaction. This work provides a body of the evidence for the correct channel identification and for the absence of the 6H resonances at energy ET = 0 − 3.5 MeV above the 3H+3n decay threshold. In addition the first strong experimental evidence is given that the 6H → 5H*+n → 3H+3n sequential decay is the dominating 6H decay channel.