Instrument : Absolute Solar Transmittance Interferometer (ASTI)
Instrument Categories
Radiometric
General Overview
The absolute solar transmittance interferometer (ASTI) provides calibrated spectra of the solar irradiance at the surface of the earth over a wavelength region from 1 to 5 microns at a resolution of 2 wavenumbers. The system consists of a BOMEM MB-120 interferometer equipped with a CaF2 beamsplitter and an InSb detector. The interferometer is coupled with a scanning mirror and automated solar-tracking system permitting collection of relative solar irradiance spectra throughout the day. Periodic calibration against a NIST standard lamp source yields absolute solar irradiance at the surface of the earth.
Primary Measurements
The following measurements are those considered scientifically relevant.
Contact(s)
Douglas Sisterson
(630) 252-5836
dlsisterson@anl.gov
