Abstract

The World Radiometric Reference (WRR) is an artefact based reference for Direct Solar Irradiance (DSI) measurements. The WRR is realized by a group of electrical substitution radiometers, the World Standard Group (WSG). In recent years, a relative difference of about -0.3% between the International System of Units (SI) scale and the WRR scale was observed with the SI scale being lower. The Cryogenic Solar Absolute Radiometer (CSAR) aims for i) providing direct traceability of DSI measurements to the SI system, ii) reducing the overall uncertainty of DSI measurements towards 0.01% and for iii) replacing the WSG in future. The latest SI-WRR intercomparisons performed with CSAR revealed a relative difference of -0.29% ± 0.064% (k = 1) between the SI and the WRR scale, a result that agrees well with previous findings. The uncertainty of corrections for the window transmittance results currently in the largest contribution to the total uncertainty for the CSAR measurements. The formal transition from the WRR t...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.