Consultative committee on ionizing radiation: Impact on radionuclide metrology

Abstract

In response to the CIPM MRA, and to improve radioactivity measurements in the face of advancing technologies, the CIPM’s consultative committee on ionizing radiation developed a strategic approach to the realization and validation of measurement traceability for radionuclide metrology. As a consequence, measurement institutions throughout the world have devoted no small effort to establish radionuclide metrology capabilities, supported by active quality management systems and validated through prioritized participation in international comparisons, providing a varied stakeholder community with measurement confidence.

On decay constants and orbital distance to the Sun—part I: alpha decay

“…In 2009, controversy arose due to claims by Jenkins et al that seasonal effects at a level of 10 −3 in repeated decay rate measurements of 32 Si/ 36 Cl and 226 Ra were due to an annual modulation of the decay constants rather than instabilities in the detection system [17,18]. Fischbach et al postulated a causal correlation with the orbital Earth-Sun distance, possibly through interactions with solar neutrinos or a scalar field affecting the terrestrial fine structure constant [19].…”

“…As much as these claims attract interest as inspiration for new physical theories or hope for revolutionising cosmic neutrino detection and radioactive waste management [26][27][28], if true they would have major implications on traceability and equivalence in the common measurement system of radioactive substances. Primary standardisation of activity concentration of a radionuclide in solution [29,30] is performed down to an accuracy of typically 0.1% [31], and international equivalence is established through key comparisons organised under the auspices of the BIPM [32]. Through the International Reference System (SIR) [33] standardisations performed over half a century worldwide can be compared.…”