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Two determinations of the Ge-68 half-life



Denis E. Bergeron, Jeffrey T. Cessna, Brian E. Zimmerman


In nuclear medicine, 68Ge is used to generate 68Ga for imaging by positron emission tomography (PET) and sealed sources containing 68Ge/68Ga in equilibrium have been adopted as long-lived calibration surrogates for the more common PET nuclide, 18F. We prepared several 68Ge sources for measurement on a NaI(Tl) well counter and a pressurized ionization chamber, following their decay for 110 weeks (≈ 2.8 half-lives). We determined values for the 68Ge half-life of T1/2 = 271.14(14) d and T1/2 = 271.07(12) d from the NaI(Tl) well counter and ionization chamber measurements, respectively. These are in accord with the current decay data evaluation project (DDEP) evaluation value of T1/2 = 270.95(26) d and we discuss the expected impact of our measurements on the evaluated half-life.
Applied Radiation and Isotopes


Germanium-68, nuclear data, half-life, uncertainty, PET calibration, reentrant ionization chamber, NaI(Tl) well counter


Bergeron, D. , Cessna, J. and Zimmerman, B. (2017), Two determinations of the Ge-68 half-life, Applied Radiation and Isotopes, [online], (Accessed May 23, 2024)


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Created October 19, 2017, Updated November 10, 2018