RADIOMETRY AT THE NIST SURF-II STORAGE-RING FACILITY

The National Institute of Standards and Technology (NIST) in Gaithersburg, MD, is the site of the Synchrotron Ultraviolet Radiation Facility (SURF II). The synchrotron radiation from the 300 MeV electron storage ring is used for most of the NIST radiometry programs in the far ultraviolet. Continuum radiation from SURF II extends from the infrared to about 4 nm (310 eV) and is a standard source for the calibration of integrated optical systems, particularly space experiments. The SURF II facility is also used for a large portion of the NIST far ultraviolet transfer detector standards program, in which spectrally calibrated detector standards are available from 5 nm (248 eV) to 254 nm (4.9 eV). One of the most recent activities has been the development of a new apparatus designed to qualify working standards for calibration of the NIST MgF2 windowed far ultraviolet transfer standard detectors. Additionally, new radiometric quality silicon photodiodes have now been developed. These detectors offer many improvements onver NIST's photoemissive standards. © 1995 American Institute of Physics.