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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 nist-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 November 15, 2019