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¹³Be is reported to have been populated in the ¹⁴C(⁷Li, ⁸B) reaction at E(⁷Li) = 82 MeV. Its atomic mass excess is reported to be 35.0 ± 0.5 MeV and Γ = 0.9 ± 0.5 MeV (83AL20, 85AL1G). It is then unstable with respect to breakup into ¹²Be + n by 1.9 ± 0.5 MeV. However, the reported state may not be the ground state of ¹³Be (89OG1B). See also (89DE52). ¹³Be has not been observed in the interaction of 44 MeV/A ⁴⁰Ar ions on Ta, as would be expected since it is unstable (86GI10). A calculation in a (0 + 1)h-barω model suggests that the first four states of ¹³Be calculated to be at 0, 0.05, 1.28 and 1.55 MeV have J^π = 1/2^-, 5/2⁺, 5/2^- and 1/2⁺ (85PO10). See also (85GA1C, 86DO01, 86GA1J; hypernuclei), (87PE1C), (86AN07) and (87SA15, 89PO1K; theor.).