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Updated: Jun 17, 2026
09:18
Laser-heating and Radiance Spectrometry for the Study of Nuclear Materials in Conditions Simulating a Nuclear Power Plant Accident
Published on: December 14, 2017
Summary
Two new cavity-type radiometers achieve 0.3% accuracy in irradiance measurements. These instruments, based on first principles, offer reliable measurements across UV, visible, and IR spectra for scientific applications.
Area of Science:
- Radiometry
- Optical Physics
- Metrology
Background:
- Accurate irradiance measurement is crucial for various scientific disciplines.
- Existing radiometers may have limitations in accuracy or operational range.
- Cavity-type radiometers offer potential for high accuracy due to their blackbody-like properties.
Purpose of the Study:
- To develop and validate novel cavity-type radiometers with high measurement accuracy.
- To assess the performance of these radiometers across different spectral ranges and environmental conditions.
- To experimentally determine the Stefan-Boltzmann constant using a developed radiometer.
Main Methods:
- Development of two cavity-type radiometers based on first principles.
- Precise measurement of aperture area, electric voltages, and blackbody cavity absorptance (0.998-0.999).
- Operation in vacuum (<10(-5) Torr) for the first radiometer and in air or vacuum for the second.
Main Results:
- Both radiometers achieve an indicated measurement error of 0.3%.
- The first radiometer measures irradiance from 10 mW cm(-2) to 300 mW cm(-2) in vacuum.
- Experimental determination of the Stefan-Boltzmann constant showed a 0.3% deviation from the theoretical value.
Conclusions:
- The developed cavity-type radiometers provide highly accurate irradiance measurements.
- The experimental validation of the Stefan-Boltzmann constant confirms the reliability of these radiometers.
- The second radiometer offers versatile operation in air or vacuum for a broader intensity range (10-800 mW cm(-2)).
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