Facility for irradiance calibration using synchrotrons (FICUS)

The spectral irradiances of deuterium lamps from 200 nm to 400 nm are calibrated in the Facility for Irradiance Calibration Using Synchrotrons (FICUS) which is located in the Synchrotron Ultraviolet Radiation Facility III (SURF III).

A single-grating monochromator with an integrating-sphere receiver is used for the spectral irradiance calibrations of deuterium lamps from 200 nm to 400 nm.  The spectral irradiances are determined using the absolutely calculable Schwinger equation and the beam and the measurement parameters.  The deuterium lamps are calibrated against the SURF III spectral irradiances.