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An activity of τ_1/2 = 11.4 ± 0.5 msec, ascribed to ¹²Be, is observed in the GeV proton irradiation of ¹⁵N, ¹⁶O, ¹⁸O, ¹⁹F, ²³Na and ²⁷Al targets (PO65B). A peak in the particle-identifier spectrum from 5.3 GeV protons on U confirms the existence of ¹²Be, but the assignment of the 11.4 msec half-life is rendered uncertain by the discovery of ¹¹Li (PO66H). A calculation by Kurath (see ref ⁸ in (PO65B)) suggests log ft = 3.5 for the ground state; E_β^-(max) is then ~ 11.7 MeV for the above τ_1/2. (M - A) for ¹²Be is then ~ 25.1 MeV, which would mean that ¹²Be is bound with respect to ¹¹Be + n by ~ 3.2 MeV. See also (GO60P, ZE60A, BA61F, AU67A).