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Comparison of the high-temperature scales of the NMIJ and the NPL with the scale of the PTB in the temperature range from 1000 °C up to 2900 °C for measurements within the EU project HIMERT (2005)

Hartmann, Jürgen ; Anhalt, Klaus ; Hollandt, Jörg ; Machin, Graham ; Lowe, D. ; McEvoy, H. ; Sakuma, F. ; Ma, L.

A comparison of the blackbody cavities for infrared ear thermometers of NMIJ, NPL, and PTB (2005)

Hartmann, Jürgen ; Ishii, J. ; Fukuzaki, T. ; McEvoy, H.C. ; Simpson, R. ; Machin, Graham ; Gutschwager, B. ; Hollandt, Jörg

Practical Implementation of the Mise en Pratique for the Definition of the Kelvin Above the Silver Point (2010)

Hartmann, Jürgen ; Machin, Graham ; Bloembergen, P ; Anhalt, Klaus ; Sadli, M ; Saunders, P ; Wooliams, E ; Yamada, Y ; Yoon, H

The “Mise en pratique for the definition of the kelvin” (MeP-K) was established in April 2006 to be the repository of information required to perform a “practical measurement of temperature in accordance with the International System of Units (SI).” This article describes the progress made by the MeP-K HT (High Temperature Task Group) of CCT-WG5 (radiation thermometry) in drawing together the appropriate methods for accessing thermodynamic temperature above the silver point involving direct radiometric measurements on the one hand and indirect extrapolation, interpolation, and least-squares fitting on the other. An examination of the uncertainties and a brief discussion of the advantages and disadvantages of the various approaches are given. A summary of the remaining issues to be resolved concludes the article.

Comparison of the New NPL Primary Standard Ag Fixed‐Point Blackbody Source with the Primary Standard Fixed Point of PTB (2003)

Hartmann, Jürgen ; McEvoy, H.C. ; Machin, Graham ; Friedrich, R. ; Hollandt, Jörg

Above the freezing point of silver (961.78 °C), the International Temperature Scale of 1990 is defined in terms of Planck’s radiation law. The scale is maintained and disseminated using a validated and linear pyrometer in conjunction with a blackbody reference source at either the Ag, Au (1064.18 °C) or Cu (1084.62 °C) freezing point. In order to realize the scale with the highest precision high quality, well‐characterised, reproducible fixed‐point blackbody sources are required. Such sources have been maintained at NPL for a number of years, but it was felt that improvements to the design would be beneficial. A new Ag point blackbody source has therefore been constructed. The new design will improve the quality and reproducibility of the melting and freezing plateaux and reduce errors due to the ‘out‐of‐focus’ size‐of‐source effect which is difficult to measure and to eliminate. Full details of the design of the new …

A comparison of high temperature fixed-points of Pt-C and Re-C constructed by BIPM, NMIJ and NPL (2005)

Hartmann, Jürgen ; Machin, Graham ; Yamada, Y. ; Lowe, D. ; Sasajima, N. ; Anhalt, Klaus ; Goebel, R. ; McEvoy, H.C. ; Bloembergen, P.

Future perspectives for high-temperature metrology from the FP5 HIMERT project (2005)