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%I #23 Feb 22 2024 20:16:52
%S 2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,38,42,44,48,52,56,60,
%T 62,66,68,72,88,90,118,140,166,172,178,182,188,194,200,202,206,208,
%U 210,222,228,234,240,246,250
%N Even mass numbers with only one beta-stable isobar.
%C A beta-stable nuclide is a nuclide whose beta decay (beta-minus and beta-plus decay) is energetically disallowed; that is to say, a nuclide that has lower energy than its isobars with one more or one less proton. Note that double beta decay is allowed. A nuclide whose beta decay is energetially allowed, even if not observed (in the case of 48Ca, 96Zr, 123Te, 148Gd, 180mTa, 222Rn and 247Cm), is not classified as being beta-stable.
%C For even n <= 256 not being a term in this sequence, there are two beta-stable isobar with mass number n, except that there are three for n = 124, 130, 136, 150 and 154.
%C 146 is not a term because even if 146Sm is unstable, it is beta-stable (in fact having lower energy than the stable 146Nd).
%C 48 is a term because even if 48Ca is stable, it is not beta-stable.
%C Pages 14-15 of the Hiroyuki Koura link predict only one further term 298 (corresponding to 298Fl) up to 332.
%H Hiroyuki Koura, <a href="http://tan11.jinr.ru/pdf/10_Sep/S_2/05_Koura.pdf">Decay Modes and a limit of existence of nuclei</a>, 4th International Conference on the Chemistry and Physics of the Transactinide Elements. (See <a href="https://en.wikipedia.org/wiki/User:ComplexRational/Isotopes#Beta-stable_isotopes_of_superheavy_elements">here</a> for an excerpted table.)
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Beta-decay_stable_isobars">Beta-decay stable isobars</a>.
%e The corresponding nuclides are 2H, 4He, 6Li, 8Be, 10B, 12C, 14N, 16O, 18O, 20Ne, 22Ne, 24Mg, 26Mg, 28Si, 30Si, 32S, 34S, 38Ar, 42Ca, 44Ca, 48Ti, 52Cr, 56Fe, 60Ni, 62Ni, 66Zn, 68Zn, 72Ge, 88Sr, 90Zr, 118Sn, 140Ce, 166Er, 172Yb, 178Hf, 182W, 188Os, 194Pt, 200Hg, 202Hg, 206Pb, 208Pb, 210Po, 222Ra, 228Th, 234U, 240Pu, 246Cm and 250Cf.
%Y Cf. A368859 (beta-stable isotopes), A368860 (isotones), A367461 (isodiaphers)
%K nonn,fini,hard,more
%O 1,1
%A _Jianing Song_, Jan 08 2024