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Radionuclide Half-Life Measurements Data

M. P. Unterweger, D. D. Hoppes, F. J. Schima, and  J. S. Coursey

  Radionuclide   Number of  
Sources
Number of
  Half Lives  
Followed
  Half Life*  Statistical
Standard
  Uncertainty  
Other
Standard
  Uncertainty  
  References
3H183  4500 ± 8 d 801 (a)
18F313.1  1.82951 ± 0.00034 h 0.000240.00024§
22Na51.9 - 4.7  950.97 ± 0.15 d 0.090.12§
24Na141.1 - 7.6  14.9512 ± 0.0032 h 0.00090.0031§
32P22.8  14.263 ± 0.003 d 0.0030.06
44Ti10.35  22154 ± 456 d 1804192
46Sc43.6 - 10.3  83.831 ± 0.066 d 0.0300.059§
51Cr112.3 - 8.9  27.7010 ± 0.0012 d 0.00070.0009§
54Mn23.3 - 7.4  312.028 ± 0.034 d 0.0340.0§
57Co74.7 - 10.4  272.11 ± 0.26 d 0.090.25§
58Co19.1  70.77  ± 0.11 d 0.110.0§
59Fe64.0 - 9.3  44.5074 ± 0.0072 d 0.00480.0053§
60Co83.7 - 5.3  1925.20 ± 0.25 d 0.100.23§,6
62Cu32.7 - 3.9  9.6725 ± 0.0080 min 0.00800.03,6
65Zn13.2  244.164 ± 0.099 d 0.0990.0§
67Ga131.8 - 8.3  3.26154 ± 0.00054 d 0.000150.00052§
75Se192.4 - 8.7  119.809 ± 0.066 d 0.0140.065§
85Kr11.9  3935.7 ± 1.2 d 1.20.0§,6
85Sr81.1 - 4.8  64.8530 ± 0.0081 d 0.00390.0071§
88Y81.3 - 8.1  106.626 ± 0.044 d 0.0170.041§
99Mo143.6 - 9.5  65.9239 ± 0.0058 h 0.00310.0049§
99mTc332.1 - 12.0  6.00718 ± 0.00087 h 0.000150.00086§ (b)
99mTc171.9 - 8.0  6.0123 ± 0.0032 h 0.00070.00316 (c)
103Ru70.4  39.310 ± 0.044 d 0.0440.06
109Cd23.4 - 5.3  463.26 ± 0.63 d 0.360.51§
110mAg19.3  249.950 ± 0.024 d 0.0240.0§
111In111.4 - 9.3  2.80477 ± 0.00053 d 0.000170.00051§
113Sn112.3 - 11.0  115.079 ± 0.080 d 0.0250.076§
117mSn101.5 - 4.0  14.00 ± 0.05 d 0.050.04
123I35.4 - 12.7  13.2235 ± 0.0019 h 0.00190.0§
125I181.4 - 6.2  59.49  ± 0.13 d 0.030.12§
125Sb15.4  1007.56 ± 0.10 d 0.100.0§,6
127Xe51.1 - 11.5  36.3446 ± 0.0028 d 0.00280.0§
131I211.0 - 10.9  8.0197 ± 0.0022 d 0.00050.0021§
131mXe21.8  11.934 ± 0.021 d 0.0140.016§
133Ba42.0  3854.7 ± 2.8 d 1.32.5§,6
133Xe34.8 - 11.2  5.24747 ± 0.00045 d 0.000450.0§
134Cs51.7 - 3.0  753.88 ± 0.15 d 0.110.11§
137Cs60.7 - 0.9  11018.3 ± 9.5 d 3.58.8§,6
139Ce91.5 - 6.4  137.734 ± 0.091 d 0.0290.086§
140Ba101.8 - 4.4  12.7527 ± 0.0023 d 0.00090.0022§
140La24.2  40.293 ± 0.012 h 0.0080.009§
141Ce16.1  32.510 ± 0.024 d 0.0240.0§
144Ce13.9  284.534 ± 0.032 d 0.0320.0§,6
152Eu41.6 - 1.8  4947.2 ± 1.1 d 0.70.8§,6
153Gd27.3  239.472 ± 0.069 d 0.0410.055§
153Sm17.3  46.2853 ± 0.0014 h 0.00140.0§
154Eu32.4  3145.2 ± 1.1 d 1.10.0§,6
155Eu23.1 - 4.3  1739.06 ± 0.45 d 0.450.0§,6
166Ho25.4 - 7.2  26.794 ± 0.023 h 0.0130.019§,6
169Yb143.4 - 9.5  32.0147 ± 0.0093 d 0.00260.0089§
177Lu42 - 5  6.64 ± 0.01 d 0.010.05
181W35.9 - 6.6  121.095 ± 0.064 d 0.0420.048§
186Re25.7 - 6.5  89.248 ± 0.069 h 0.0180.067§
188Re34.2 - 7.1  17.001 ± 0.022 h 0.090.021§,6
188W14.0  69.783 ± 0.048 d 0.0480.06
192Ir12.4  73.810 ± 0.019 d 0.0190.0§
195Au50.6 - 6.0  186.098 ± 0.047 d 0.0210.042§
198Au44.5 - 7.4  2.69517 ± 0.00021 d 0.000210.0§
201Tl122.6 - 11.5  3.0456 ± 0.0015 d 0.00040.0014§
202Tl11.4  12.466 ± 0.081 d 0.0810.0§
203Hg141.7 - 6.6  46.619 ± 0.027 d 0.0070.026§
203Pb71.8 - 2.8  51.923 ± 0.037 h 0.0130.034§
207Bi20.9  11523. ± 15. d 912§,6
228Th61.7 - 8.3  698.60 ± 0.36 d 0.140.33§
*The stated uncertainties are the sum, in quadrature, of the statistical uncertainty (the "external standard deviation" in the weighted mean) and other uncertainties which include those from the Stevenson equation (NBS Special Publication 626) and from the correction for the 210Bi ingrowth in the radium reference sources.
(a)Measured by internal gas proportional counting.
(b)Normal saline solution.
(c)Acid solution.

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Radioactivity Group

Created September 6, 2009, Updated June 2, 2021