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
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);
    17 a-decays  (and 30 associated gs) with yields < 0.01% omitted - full details here
  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