Problems with the interpretation of the 10He ground state

The continuum of the 10He nucleus is studied theoretically in a three-body 8He+n+n model based on recent information concerning the 9He spectrum [M. S. Golovkov et al., Phys. Rev. C 76, 021605(R) (2007)]. The 10He ground state (g.s.) candidate with structure [p1/2]2 for new g.s. energy of 9He is predicted to be at about 2.0-2.3 MeV. The peak in the cross section associated with this state may be shifted to a lower energy (e.g., ∼ 1.2 MeV) when 10He is populated in reactions with 11Li due to a peculiar reaction mechanism. Formation of the low-energy (E<250 keV) 'alternative' ground state with structure [s1/2]2 is highly probable in 10He when there is considerable attraction (e.g., a<-5 fm) in the s-wave 9He channel, whose properties are still quite uncertain. This result either questions the existing experimental low-energy spectrum of 10He or places a limit on the scattering length in the 9He channel, which contradicts existing data