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Thermodynamic Radiation Thermometry for the Next SI



Howard W. Yoon, Charles E. Gibson, V B. Khromchenko, George P. Eppeldauer, Robert R. Bousquet, Steven W. Brown, Keith R. Lykke


We describe the construction, the calibration and the use of the NIST Thermodynamic Radiation Thermometer (TRT) to measure the temperature of the gold-freezing temperature blackbody and a variable-temperature blackbody from 800 ?C to 2700 ?C. These temperature determinations are detector-based and derived from the electrical substitution radiometer and length units. The TRT is constructed using a cooled, near-infrared enhanced silicon detector with a room-temperature-stabilized 5-position filter wheel. The characteristics of the TRT, such as the size-of-source effect and preamplifier linearity, are determined. The measured temperatures are compared with those obtained using the NIST Absolute Pyrometer 1 (AP1) and the current NIST standard radiation thermometer, the Photo-electric Pyrometer (PEP). After the performance assessments, the TRT will become the standard radiation thermometer for disseminating radiance temperature scales in the United States.
International Journal of Thermophysics


gold freezing temperature, kelvin, linearity, radiometric temperatures, thermodynamic temperatures


Yoon, H. , Gibson, C. , Khromchenko, V. , Eppeldauer, G. , Bousquet, R. , Brown, S. and Lykke, K. (2007), Thermodynamic Radiation Thermometry for the Next SI, International Journal of Thermophysics (Accessed April 21, 2024)
Created November 15, 2007, Updated June 26, 2017