A New Generation High-Temperature Blackbody and Synchrotron Radiation Facility and Its Application in Extraterrestrial Solar Spectral Irradiance Measurements

Under the impetus of extraterrestrial solar spectral irradiance measurement and atmospheric quantitative remote sensing, spectroradiometry technology makes a rapid progress internationally in recent years. Based on the advanced high temperature technology, excellent pyrolytic graphite materials and unique designs, All-Russian Research Institute for Optical Physical Measurements (VNIIOFI) successfully developed large area Planck high temperature blackbody sources with temperature as high as 3 200 similar to 3 500 K which had the high uniform and high stable radiation characteristics. By means of filter radiometer calibrated by absolute cryogenic radiometer (ACR), the new iteration temperature measurement technology of high temperature blackbodies made the temperature uncertainty less than 0. 5 K. At PTB, high temperature blackbody was directly used for the calibration of solar spectral irradiance measurement instruments, SOLSPEC, on board International Space Station and the uncertainty of calibration was less than 0. 5%similar to 1%. The new generation electron storage ring Metrology Light Source (MLS) was set up at PTB in 2008. The electron energy for stable ring operation could be set to any value from 105 to 630 MeV, giving a high flexibility in adjusting the SR spectrum. Through this operation, the characteristic wavelength of the radiation emission could be shifted from 735 nm to 3. 4 nm. In order to change the synchrotron light intensity without changing the spectrum, the electron beam current could be adjusted within a range of more than 11 decades, i. e. from one stored electron which was equivalent to the current of 1 pA to the design value of 200 mA. At NIST, the FICUS (Facility for Irradiance Calibration Using Synchrotron) was built on beamline 3 at SURF (Synchrotron Ultraviolet Radiation Facility) using for the calibration of ultraviolet spectral irradiance transfer standard deuterium lamp. The uncertainty of the 200nm-400nm spectral irradiance was 1. 2% (k=2). The new generation synchrotron radiation facilities laid the technical foundations for the high precision calibration of solar spectral irradiance measurement instruments in short wavelength such as SBUV, SUSIM, SOLSTICE, SIM and SOLSPEC. This paper described the establishment and development of the new generation high temperature blackbody and synchrotron radiation facilities, spectral radiance standard and spectral irradiance standard transfer and international comparison, and reviewed their application in solar spectral irradiance measurements.