228 Ac decay; t1/2 = 6.15 h (t = 8.87 h).

  1. 228Ac [b (+ g)] 228Th  (~ 100%)
  2. 228Ac [a (+ g)] 224Fr (5.5 × 10-6%; t1/2 ~ 13 ky)
g + c.e.(a) a b
E(b) I(c) (c) Ic.e. E(b) I(c) E(b) I(c)
1631.0 0.016 1.6 × 10-5     454.0 0.026
1502.0 0.0047 4.7 × 10-6     "  
814.0 7.2 × 10-5 2.9 × 10-7     "  
672.0 2.7 × 10-4 1.6 × 10-6     "  
42.5 9.3 × 10-5 0.0046     "  
1588.0 0.033 3.3 × 10-5     496.0 0.042
1459.0 0.0080 1.6 × 10-5     "  
1250.0 6.4 × 10-4 1.3 × 10-6     "  
677.0 6.4 × 10-4 1.4 × 10-5     "  
666.0 6.4 × 10-4 3.8 × 10-5     "  
629.0 4.6 × 10-4 3.2 × 10-5     "  
623.0 1.1 × 10-4 7.7 × 10-7     "  
555.0 4.7 × 10-4 4.7 × 10-5     "  
523.0 0.0011 1.2 × 10-5     "  
492.0 2.4 × 10-4 3.4 × 10-5     "  
419.0 2.1 × 10-4 4.2 × 10-6     "  
115.0 1.0 × 10-4 1.0 × 10-3     "  
1345.0 9.3 × 10-5 1.9 × 10-7     611.0 0.081
1135.0 1.0 × 10-4 2.0 × 10-7     "  
562.0 0.0087 5.6 × 10-4     "  
509.0 0.0047 5.6 × 10-4     "  
440.0 0.0013 3.9 × 10-4     "  
378.0 2.5 × 10-4 7.0 × 10-5     "  
99.5 0.013 0.053     "  
1374.0 1.4 × 10-4 2.8 × 10-7     710.0 0.0090
1245.0 9.8 × 10-4 2.0 × 10-6     "  
1103.0 1.5 × 10-4 3.1 × 10-7     "  
463.0 0.044 0.0023     "  
452.0 1.6 × 10-4 2.6 × 10-5     "  
409.0 0.019 0.0016     "  
341.0 0.0038 4.5 × 10-4     "  
264.0 4.1 × 10-4 2.1 × 10-5     "  
1111.0 0.0031 6.3 × 10-6     974.0 0.035
840.0 0.0094 1.3 × 10-4     "  
772.0 0.015 4.1 × 10-4     "  
649.0 4.1 × 10-4 1.0 × 10-5     "  
199.0 0.0033 3.1 × 10-4     "  
146.0 0.0016 0.0032     "  
77.3 2.6 × 10-4 6.1 × 10-5     "  
1154.0 0.0014 2.9 × 10-6     989.0 0.056
1096.0 0.0013 4.0 × 10-6     "  
322.0 0.0023 3.3 × 10-4     "  
279.0 0.0020 0.0013     "  
185.0 7.2 × 10-4 0.046     "  
174.0 3.6 × 10-4 9.0 × 10-4     "  
1065.0 0.0014 4.1 × 10-6     1019 0.058
795.0 0.043 8.7 × 10-4     "  
727.0 0.0064 1.2 × 10-4     "  
154.0 0.0074 0.0013     "  
100.0 9.6 × 10-4 6.0 × 10-4     "  
965.0 0.051 5.6 × 10-4     1119 0.030
836.0 0.017 2.4 × 10-4     "  
969.0 0.162 0.0017     1173 0.310
911.0 0.266 0.0032     "  
782.0 0.0050 1.5 × 10-4     "  
338.0 0.113 0.0033     1746 0.116
209.0 0.039 0.0033     "  
328.0 0.030 9.1 × 10-4     1814 0.0054
270.0 0.034 0.0016     "  
129.0 0.025 0.093     1955 0.019
57.8 0.0049 0.760     2084 0.100
? ? ? 4270 5.5 × 10-8    

Notes:                                                                     

  1. c.e.: conversion electrons
  2. Energies in keV
  3. Intensities per `parent' decay of Th
  4. Data from compilations and amendments in Nuclear Data Sheets to Vol. 64 (1991);
    37 b-decays and 4 other levels (and 160 associated gs) with branching ratio < 2% omitted - full details here
  5. 228Ac and 224Fr entries in KAERI nuclide chart