At the 16th General Conference of Weights and Measures (CGPM) in November 2018 it was agreed that the international system of units would be redefined in terms of defined values of fundamental constants. For the kelvin the redefinition will be in terms of a defined value of the Boltzmann constant.
To facilitate an effective redefinition it is essential that the required primary thermometry methods are in place. Through the development of reliable primary thermometry at the extremes of temperature (<25 K and >1300 K) it is envisaged that by the mid-2020s the current temperature scales (ITS-90 and PLTS-2000) will be superseded by practical primary thermometry.
The overall objective of this research project is to optimise the primary thermometry capability within the EU. It exploits synergies between EU partners and ex-EU partners to ensure, as we approach and implement and realise the kelvin redefinition, the EU grows its scientific leadership position in this unit area.
This work is part of the EMPIR project INK2.