Principal gs in natural U decay chain.

Table (1) below lists the 20 most intense gs from the natural U decay chains (in equilibrium). These are the lines most likely to be observed from U external to detectors. Table (2) lists these lines in order of energy.

For U within detectors, effective intensities must include any conversion electrons - Table (3) - and observed energies will be modified by the coincident a or b decays.

(1) by g intensity

 blank.gif (43 bytes)

(2) by g energy
 
g a b from
I(c) E(b) (a,c) Ic.e. E(b) E(b)
0.428 609.0 0.009   2665 214Bi
0.342 352.0 0.102   670.0 214Pb
0.177 295.0 0.083   730.0 214Pb
0.147 1765 7.6 × 10-4   1510 214Bi
0.141 1120 0.002   1545 214Bi
0.072 242.0 0.057   730.0 214Pb
0.056 1238 7.1 × 10-4   1427 214Bi
0.046 2204 1.5 × 10-4   1070 214Bi
0.046 768.0 7.4 × 10-4   1897 214Bi
0.043 63.3 0.018   106.0 234Th
0.039 46.5 0.726   17.0 210Pb
0.037 1378 1.5 × 10-4   1897 214Bi
0.035 186.0 0.024 4602   226Ra
0.029 934.0 7.2 × 10-4   1731 214Bi
0.028 1730 7.3 × 10-5   1545 214Bi
0.027 1408 1.0 × 10-4   1257 214Bi
0.025 186.0 0.003 4414   235U
0.025 92.4 0.140   106.0 234Th
0.024 92.8 0.004   106.0 234Th
0.020 1509 1.4 × 10-4   1156 214Bi
 
g a b from
E(b) I(c) (a,c) Ic.e. E(b) E(b)
46.5 0.039 0.726   17.0 210Pb
63.3 0.043 0.018   106.0 234Th
92.4 0.025 0.140   106.0 234Th
92.8 0.024 0.004   106.0 234Th
186.0 0.035 0.024 4602   226Ra
186.0 0.025 0.003 4414   235U
242.0 0.072 0.057   730.0 214Pb
295.0 0.177 0.083   730.0 214Pb
352.0 0.342 0.102   670.0 214Pb
609.0 0.428 0.009   2665 214Bi
768.0 0.046 7.4 × 10-4   1897 214Bi
934.0 0.029 7.2 × 10-4   1731 214Bi
1120 0.141 0.002   1545 214Bi
1238 0.056 7.1 × 10-4   1427 214Bi
1378 0.037 1.5 × 10-4   1897 214Bi
1408 0.027 1.0 × 10-4   1257 214Bi
1509 0.020 1.4 × 10-4   1156 214Bi
1730 0.028 7.3 × 10-5   1545 214Bi
1765 0.147 7.6 × 10-4   1510 214Bi
2204 0.046 1.5 × 10-4   1070 214Bi

(3) by g + conversion electron intensity

g + c.e. a b from
I(c) E(b) E(b) E(b)
0.765 46.5   17.0 210Pb
0.444 352.0   670.0 214Pb
0.437 609.0   2665 214Bi
0.349 53.2 4723   234U
0.278 67.7 4621   230Th
0.260 295.0   730.0 214Pb
0.185 49.6 4147   238U
0.164 92.4   106.0 234Th
0.147 1765   1510 214Bi
0.144 1120   1545 214Bi
0.128 242.0   730.0 214Pb
0.121 53.2   972.0 214Pb
0.062 29.5   169.0 234Th
0.060 63.3   106.0 234Th
0.060 186.0 4602   226Ra
0.057 1238   1427 214Bi
0.047 768.0   1897 214Bi
0.047 2204   1070 214Bi
0.038 1378   1897 214Bi
0.035 25.6   305.0 231Th

 

Total decays, chain in equilibrium: 2.197 g, 2.578 c.e., 7.958 a, 5.917 b.

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)