Title :
Evaluation of sealed type cell of indium point in NMIJ
Author :
Tamba, J. ; Koizumi, K. ; Sakai, M. ; Sato, K. ; Kishimoto, I. ; Arai, M.
Author_Institution :
Nat. Metrology Inst. of Japan, National Inst. of Adv. Industrial Sci. & Technol., Ibaraki, Japan
Abstract :
The freezing point of indium is one of the temperature fixed points defined in the ITS-90. An open type cell of indium is used as the national standard and a sealed type cell as a working standard in NMIJ. The realized temperatures of those cells have been compared with each other almost yearly since 1997. The temperature difference and the comparison uncertainty were investigated. The freezing temperature of the sealed type cell is 1.27 mK higher than that of the open type cell with the comparison uncertainty of 0.19 mK in 2003. The change of the temperature difference during the past six years is still tolerable.
Keywords :
calibration; freezing; indium; temperature measurement; temperature scales; 0.19 mK; 1.27 mK; National Metrology Institute of Japan; freezing temperature; indium point; national standard; sealed type cell;
Conference_Titel :
SICE 2003 Annual Conference
Conference_Location :
Fukui, Japan
Print_ISBN :
0-7803-8352-4
