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Radionuclide Half-Life Measurements - Version History

Example of how to reference this online database: (Replace year, month day with database access date.)
Unterweger, M.P. (2003), Radionuclide Half-Life Measurements at the National Institute of Standards and Technology (version 3.0). [Online] Available: [year, month day]. National Institute of Standards and Technology, Gaithersburg, MD.
Citation Form:
Author/editor (Year), Title (edition). [Type of medium] Available: URL [Access date].


Version 3.0
April 2003
   Radionuclides 32P, 99mTc (acid), 103Ru, and 188W were added; and the values for 60Co, 62Cu, 85Kr, 125Sb, 133Ba, 137Cs, 144Ce, 152Eu, 154Eu, 155Eu, 166Ho, 188Re, and 207Bi and the associated references were changed.
Version 2.1
August 2000
The value of the half-life of 3H (tritium) was improved from 4504 ± 9 d to 4500 ± 8 d, and the associated reference was changed.
Version 2.0
July 1999
Radionuclides 3H, 44Ti, 62Cu, 117mSn, and 177Lu were added and the layout was redesigned.
Version 1.0
May 1997
Available online.
NBS SP 626
D.D. Hoppes and F.J. Schima
NBS Special Publication 626
Created July 29, 2009, Updated September 26, 2016