227 Ac decay; t1/2 = 21.77 y (t = 31.41 y).

  1. 227Ac [b (+ g)] 227Th   (98.62%; t1/2 = 22.07 y)
  2. 227Ac [a (+ g)] 223Fr   (1.38%;   t1/2 = 1578 y)
g + c.e.(a) a b
E(b) I(c) (c) Ic.e. E(b) I(c) E(b) I(c)
24.5 3.1 × 10-6 2.6 × 10-4     19.0 0.0026
15.2 8.0 × 10-6 0.0024     "  
9.3 5.0 × 10-6 0.018     34.0 0.016
          43.5 0.025
359.0 1.8 × 10-8 4.0 × 10-10 4360 1.8 × 10-8    
319.0 3.5 × 10-8 1.1 × 10-9 4420 3.7 × 10-8    
435.0 3.0 × 10-7 4.5 × 10-9 4442 3.0 × 10-7    
369.0 3.0 × 10-8 6.6 × 10-10 4456 3.0 × 10-8    
69.5 1.4 × 10-8 4.1 × 10-9 4509 1.8 × 10-8    
246.0 3.4 × 10-8 1.9 × 10-9 4578 1.8 × 10-8    
357.0 5.7 × 10-8 1.4 × 10-9 4586 6.2 × 10-8    
352.0 5.7 × 10-8 1.4 × 10-9 4591 1.2 × 10-7    
121.0 4.8 × 10-8 1.5 × 10-8 "      
190.0 3.0 × 10-7 2.1 × 10-7 4712 1.8 × 10-5    
144.0 1.2 × 10-7 2.5 × 10-8 "      
84.0 1.0 × 10-6 1.8 × 10-7 "      
162.0 5.3 × 10-8 7.9 × 10-9 4735 4.8 × 10-7    
46.5 2.5 × 10-7 2.1 × 10-7 "      
172.0 1.8 × 10-6 2.3 × 10-7 4766 1.0 × 10-5    
134.0 1.2 × 10-6 2.8 × 10-7 "      
27.0 1.5 × 10-6 5.2 × 10-6 "      
159.0 5.3 × 10-8 8.5 × 10-9 4782 4.8 × 10-7    
70.2 7.0 × 10-7 2.0 × 10-7 "      
160.0 8.4 × 10-6 1.3 × 10-6 4793 5.3 × 10-6    
147.0 4.3 × 10-6 8.2 × 10-7 "      
106.0 6.2 × 10-7 2.6 × 10-7 "      
121.0 1.5 × 10-7 4.4 × 10-8 4819 4.8 × 10-7    
81.1 3.0 × 10-7 5.8 × 10-8 "      
100.0 1.4 × 10-5 1.5 × 10-6 4853 2.6 × 10-5    
87.5 5.3 × 10-6 2.1 × 10-6 "      
84.0 8.8 × 10-6 1.5 × 10-6 4870 3.8 × 10-5    
70.2 6.6 × 10-6 1.8 × 10-6 "      
28.8 5.3 × 10-9 1.9 × 10-5 "      
54.0 1.4 × 10-7 2.4 × 10-5 4897 7.9 × 10-7    
12.7 9.7 × 10-8 2.5 × 10-4 4938 2.3 × 10-4    
      4950 2.9 × 10-4    

Notes:                                                                     

  1. c.e.: conversion electrons
  2. Energies in keV
  3. Intensities per `parent' decay of natural U (i.e. 0.956 238U, 0.044 235U)
  4. Data from compilations and amendments in Nuclear Data Sheets to Vol. 64 (1991)
  5. g and conversion electron intensities are totals from given level; part may be associated with different (lower energy) primaries
  6. 227Ac entry in KAERI nuclide chart