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²⁰Mg has been populated in the ²⁴Mg(α, ⁸He) reaction at E_α = 127 and 156 MeV and in the ²⁰Ne(³He, 3n) reaction at E(³He) = 70 MeV. The super-allowed decay of ²⁰Mg to the first T = 2 (J^π = 0⁺) state of ²⁰Na [E_x = 6.57 ± 0.05 MeV] has been reported from observations of the subsequent decay of that state by proton emission [see Fig. 12]. The partial half-life is 95⁺⁸⁰_-50 msec leading to a branching ratio of (3 ± 2)% for the super-allowed decay; log ft = 3.18. The results for A = 20 are in agreement with the quadratic form of the IMME: see (78AJ03, 83AJ01). See also (AN85E, AN86U) and (AN83D; theor.).