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SI-Traceable Calibrations of Celestial Objects



Keith R. Lykke, Claire E. Cramer, John T. Woodward IV


Photometric calibration is currently the leading source of systematic uncertainty in supernova surveys that aim to determine the nature of dark energy. The bulk of this uncertainty is due to imperfect knowledge of the spectral energy distribution of stars used as primary standards. We review the challenges associated with establishing an absolute calibration of stellar spectra and describe how it is possible to do better by using recent advances in optical metrology, paying particular attention to the measurement chain establishing SI-traceability and reporting of measurement uncertainties.
Proceedings Title
Calibrating Large Astronomical Surveys and Future Facilities, held at Fermilab.
Conference Dates
April 16-19, 2012
Conference Location
Batavia, IL
Conference Title
SI-Traceable Calibrations of Celestial Objects


Calibration, Optical Radiation, Photometry, Standard Star, Stellar Spectra


Lykke, K. , Cramer, C. and Woodward, J. (2015), SI-Traceable Calibrations of Celestial Objects, Calibrating Large Astronomical Surveys and Future Facilities, held at Fermilab., Batavia, IL (Accessed April 13, 2024)
Created May 14, 2015, Updated February 19, 2017