Report from the Mise en Pratique Task Group: the next international temperature scale and the mise en pratique for the definition of the kelvin
Dean C. Ripple, Bernd Fellmuth, Joachim Fischer, Graham Machin, PPM Steur, Osamu Tamura, Rod D. White
The Consultative Committee for Thermometry has asked Working Group 1 to coordinate a task group formulating an assessment and possible work plan for the next International Temperature Scale and to prepare and maintain the mise en pratique for the definition of the kelvin. In response to this charge, the Mise-en-Pratique Task Group has produced the present document. We begin by reviewing the status of the mise en pratique for the definition of the kelvin (MePK). We anticipate adding sections on supplementary information for the Provisional Low Temperature Scale of 2000 (PLTS-2000); low-temperature gas thermometry, absolute radiation thermometry, and the known differences between thermodynamic temperature T and temperature on the International Temperature Scale of 1990 (ITS-90), T90. Considering the relationship of the MePK with both the International Temperature Scales and the thermodynamic temperature scale, we anticipate a period during which temperatures are disseminated on the thermodynamic temperature scale as well as the ITS-90 and the PLTS-2000. After considering the prospects for a new international temperature scale, we conclude that a new scale should not be implemented until all technical issues are solved, and a proposed new scale tested. The report concludes with a list of outstanding issues for the Consultative Committee on Thermometry to consider.
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