The unbound isotopes 9,10He

Further insights into the reactionBe14(CH2,X)He10Jones1, Kohley2, Baumann3 et al. 2015Phys. Rev. C9010View full textAdd to dashboardCite

“…This reaction was considered to be more dissipative than the one-proton removal reaction and thus the invariant mass spectrum should not be influenced by the proposed initial state effects. We measured a resonance energy of 1.60 (25) MeV [1] consistent with the GSI results [4] but in disagreement with the Dubna data [3].…”

“…We consider both the decay of the ground (0 + ) and first excited (2 + ) state of 10 He through three states in 9 He: the 1/2 + , 1/2 − , and 3/2 − states. The 1/2 − state was fixed in energy and width at E = 1.33 MeV, Γ = 0.1 MeV [4]. Additionally, the widths of the 1/2 + and 3/2 − states were fixed at 8.4 MeV 8 He + 1n gated on multiplicity = 1, (c) 8 He + 2n, (d) 8 He + 2n gated on multiplicity = 2, (e) 8 He + 2n with causality cuts, and (f) the multiplicity distribution.…”

“…and 0.7 MeV [4,14], respectively, but allowed to vary in energy. For 10 He, both states were allowed to vary in energy.…”

“…While a missing mass measurement at Dubna using a (t, p) reaction had reported the ground state to be at 2.1(2) MeV [3], a one-proton removal reaction at GSI from a high-energy 11 Li beam found the ground state to be at a lower energy of 1.54(11) MeV [4]. Subsequently, Grigorenko and Zhukov showed that the observed peak in the 3-body spectrum of the GSI invariant mass measurement could result from the halo nature of the 11 Li projectile [2], apparently reconciling the descrepancy between the GSI and Dubna results.…”

Search for 21C and constraints on 22C

“…It is clear that any low lying s-wave state would have been apparent in the decay energy spectrum. The small magnitude of the extracted scattering length of a s = −0.05 fm is essentially equivalent to no interaction at all, thus quoting a resonance energy is not meaningful [32].…”