Normal incidence spectrophotometer using high density transmission grating technology and highly efficiency silicon photodiodes for absolute solar EUV irradiance measurementsNew developments in transmission grating and photodiode technology now make it possible to realize spectrometers in the extreme ultraviolet (EUV) spectral region (wavelengths less than 1000 A) which are expected to be virtually constant in their diffraction and detector properties. Time dependent effects associated with reflection gratings are eliminated through the use of free standing transmission gratings. These gratings together with recently developed and highly stable EUV photodiodes have been utilized to construct a highly stable normal incidence spectrophotometer to monitor the variability and absolute intensity of the solar 304 A line. Owing to its low weight and compactness, such a spectrometer will be a valuable tool for providing absolute solar irradiance throughout the EUV. This novel instrument will also be useful for cross-calibrating other EUV flight instruments and will be flown on a series of Hitchhiker Shuttle Flights and on SOHO. A preliminary version of this instrument has been fabricated and characterized, and the results are described.
Ogawa, H. S. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Mcmullin, D. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Judge, D. L. (Southern California Univ. Los Angeles, CA, United States)
Korde, R. (International Radiation Detectors Torrance, CA, United States)
August 16, 2013
January 1, 1992
Publication: In: Instrumentation for planetary and terrestrial atmospheric remote sensing; Proceedings of the Meeting, San Diego, CA, July 23, 24, 1992 (A93-27076 09-35)