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CCT Key Comparison No 1 (CCT-K1): Realisations of the ITS-90, 0.65 K to 24.5561 K, Using Rhodium-Iron Resistance Thermometers



R L. Rusby, Christopher W. Meyer, Weston L. Tew, D I. Head, K D. Hill, O Tamura, P A. de Groot, B Fellmuth, A Storm, A Peruzzi, J Engert, D N. Astrov, Y Dedikov, G A. Kytin


At its meeting in 1996 the CCT initiated five Key Comparisons to test the equivalence of realisations of the ITS-90 between National Measurement Institutes. CCT-K1 covers the temperature range from 0.65 K to 24.5561 K, in which the ITS-90 is defined by specified vapour-pressure nist-equations for 3He (0.65 K to 3.2 K) and 4He (1.25 K to 5.0 K) and interpolation nist-equations for a constant-volume gas thermometer (ICVGT) using 3He or 4He (3 K to 24.5561 K). The comparison was carried out using rhodium-iron resistance thermometers from the seven participating laboratories represented by the authors. The measurements were made in two experiments at NPL, which also coordinated the comparison.
Proceedings Title
TEMPMEKO 2004: 9th International Symposium on Temperature and Thermal Measurements in Industry and Science
Conference Dates
June 22-25, 2004
Conference Location
Cavtat - Dubrovnik , -1


gas thermometry, helium vapor pressures, ITS-90, key comparison, resistance thermometry, temperature scales, thermometry
Created June 1, 2004, Updated February 19, 2017