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11N (1990AJ01)(See the Isobar Diagram for 11N) The 14N(3He, 6He)11N reaction has been studied at E(3He) = 70 MeV. A 6He group is observed which corresponds to a state in 11N with an atomic mass excess of 25.23 ± 0.10 MeV and Γ = 740 ± 100 keV. The cross section for forming this state is 0.5 μb/sr at 10°. The observed state is interpreted as being the Jπ = 1/2- mirror of 11Be*(0.32) because of its width; the 1/2+ mirror 11Beg.s. would be expected to be much broader (1974BE20). This 11N state is unbound with respect to decay into 10C + p by 2.24 MeV. (1988WA18) adopt an atomic mass excess of 24.89 ± 0.14 MeV for 11Ng.s. [This value assumes that the first excited state in 11N is at Ex = 0.34 MeV.] We suggest an uncertainty of ± 0.2 MeV because the Ex of the first excited state in 11N may be depressed relative to 11Be*. The ground state is then unstable with respect to 10C + p by 1.90 MeV. See also (1985AN28, 1986AN07; theor.).
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