Currently temperature measurements are traceable to the 1990 International Temperature Scale (ITS-90) or the 2000 Provisional Low Temperature Scale (PLTS-2000) below 1 K. These scales have an empirical basis and are based on a series of fixed points whose temperatures have been determined a priori by primary methods.


Extension of primary thermometry


Fin here the detailled description of the project:

Publications and communications

WOOLLIAMS E., ANHALT, K.,  BALLICO, M., BLOEMBERGEN, P., BOURSON, F., BRIAUDEAU, S., CAMPOS, J., COX, M. G., DEL CAMPO, D., DURY, M.R., GAVRILOV, V., GRIGORYEVA, I., HERNANDEZ, M.L., JAHAN, F., KHLEVNOY, B., KHROMCHENKO, V.,  LOWE, D.H., LU, X., MACHIN, G., MANTILLA, J.M., MARTIN, M.J., MCEVOY, H.C., ROUGIÉ, B., SADLI, M., SALIM, S.G.,  SASAJIMA, N., TAUBERT, D.R., TODD, A., VAN DEN BOSSCHE, R., VAN DER HAM, E., WANG, T., WEI, D., WHITTAM, A., WILTHAN, B., WOODS, D.,  WOODWARD, J., YAMADA, Y., YAMAGUCHI, Y., YOON, H. and YUAN, Z.,Thermodynamic temperature assignment to the point of inflection of the melting curve of high temperature fixed points”, Philos Trans A Math Phys Eng Sci., 2016, DOI: 10.1098/rsta.2015.0044.

SADLI M., MACHIN G., ANHALT K., BOURSON F., BRIAUDEAU S., DEL CAMPO D., DIRIL A., KOZLOVA O., LOWE D.H., MANTILLA AMOR J. M., MARTIN M. J., MCEVOY H., OJANEN-SALORANTA M., PEHLIVAN Ö., ROUGIÉ B. and SALIM S. G. R., “Dissemination of thermodynamic temperature above the freezing point of silver”, Philos Trans A Math Phys Eng Sci., 2016, DOI: 10.1098/rsta.2015.0043

YAMADA Y.,  ANHALT K., BATTUELLO M., BLOEMBERGEN P., KHLEVNOY B., MACHIN G., MATVEYEV M., SADLI M., TODD A. and WANG T.,Evaluation and Selection of High-Temperature Fixed-Point Cells for Thermodynamic Temperature Assignment”, Int J Thermophys, 36, 2015, 1834-1847, DOI: 10.1007/s10765-015-1860-0

YANG I., PITRE L., MOLDOVER M.R, ZHANG J., FENG X. and SEOG K. JIN., “Improving acoustic determinations of the Boltzmann constant with mass spectrometer measurements of the molar mass of argon”, Metrologia, 52, 2015, 394–403.

GAVIOSO R. M., MADONNA RIPA D., M. STEUR P. P., GAISER C.  , ZANDT T., FELLMUTH B., DE PODESTA M., UNDERWOOD R., SUTTON G., PITRE L., SPARASCI F., RISEGARI L., GIANFRANI L., CASTRILLO A. and MACHIN G., “Progress towards the determination of the thermodynamic temperature with ultra-low uncertainty”, Phil. Trans. R. Soc. A374, 2016, 20150046 DOI: 10.1098/rsta.2015.0046

MOLDOVER M.R., GAVIOSO R.M., MEHL J.B., PITRE L., DE PODESTA M. and ZHANG J.T., “Acoustic gas thermometry”, Metrologia, 51, 2014, DOI: 10.1088/0026-1394/51/1/R1.

SADLI M., ANHALT K., BOURSON F., BRIAUDEAU S., DEL CAMPO D., DIRIL A., KOZLOVA O., LOWE D., MACHIN G., MANTILLA AMOR J.M., MARTIN M.-J., MC EVOY H., OJANEN M., PEHLIVAN Ö., ROUGIE B. and SALIM S.G.R., “Experimental assessment of thermodynamic temperature dissemination methods at the highest temperatures”, 17e Congrès international de métrologie, Paris, France, September 21st-24th 2015, DOI: 10.1051/metrology/201515017

MACHIN G., ENGERT J.; GAVIOSO R., SADLI M. and WOOLLIAMS E., “The Euramet Metrology Research Programme Project: Implementing the new kelvin (InK)”, 5th All-Russian and COOMET Member Countries Conference “Temperature-2015”, St Petersburg, Russian Federation, April 21st-24th 2015.

SADLI M., MACHIN G., ANHALT K., BOURSON F., BRIAUDEAU S., DEL CAMPO D., DIRIL A., KOZLOVA O., LOWE D., MANTILLA AMOR J. M., MARTIN M., MCEVOY H.C., OJANEN M., PEHLIVAN Ö., ROUGIÉ B. and SALIM S.G.R., “Dissemination of thermodynamic temperature above the silver freezing point temperature”, Towards implementing the new kelvin – The Royal Society, Newport Pagnell, United Kingdom, May 18th-19th 2015.

BOURSON F., BRIAUDEAU S., SALIM S.G.R., ROUGIE B., TRUONG D., KOZLOVA O. and SADLI M., “Radiometric temperature measurements on high-temperature fixed points at LNE-Cnam”, Towards implementing the new kelvin – The Royal Society, Newport Pagnell, United Kingdom, May 18th-19th 2015.

PITRE L., SPARASCI F., RISEGARI L. and TRUONG D., “Acoustic thermometry: new results from 77 K to 303 K at LNE-CNAM”, Tempmeko 2013, Funchal, Madeira, Portugal, October 14th-18th 2013.

RISEGARI L. ET TRUONG D., PITRE L, SPARASCI F, TRUONG D, VERGÉ A. and BUÉE B.,  “ACOUSTIC GAS THERMOMETER BELOW 4K: FIRST TESTS” (379), Tempmeko 2013, Madeira, Portugal, October 14th-18th 2013.


  • NPL,
  • CEM,
  • CNAM,
  • CSIC,
  • INRIM,
  • LNE,
  • MIKES,
  • PTB,
  • UVa,
  • NRC,
  • NIST,
  • KRISS,
  • UC,
  • IPC

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