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²⁰C has been observed in the fragmentation of 60 MeV/A argon ions: its mass excess is 37.20 ± 1.13 MeV (GI87B). It is then stable with respect to ¹⁹C + n and ¹⁸C + 2n by 3.3 and 3.9 MeV, respectively. See also (78AJ03, 83AJ01). The half-life of ²⁰C is calculated to be 9.3 x 10^-3 sec (KL84A). See also (AN85A, LA85I, AN86U, GU86H) and (AV82A, AN83D, SA87G; theor.).