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Foukal, Peter V.

Publications and source records attributed to Foukal, Peter V..

Solar astronomy

An overview is given of modern solar physics. Topics covered include the solar interior, the solar surface, the solar atmosphere, the Large Earth-based Solar Telescope (LEST), the Orbiting Solar Laboratory, the High Energy Solar Physics mission, the Space Exploration Initiative, solar-terrestrial physics, and adaptive optics. Policy and related programmatic recommendations are given for university research and education, facilitating solar research, and integrated support for solar research.

Rosner, Robert

The program on radiative inputs of the sun to the Earth (rise)

General concerns about changes in the Earth's climate and in the ozone layer have increased the importance of measuring and understanding variations in the sun's radiative outputs. These outputs appear, for instance, at the top of the list of global change forcing agents in the recent FY-90 document on the U.S. Global Change Program. Significant advances have been made over the past decade in radiometry of the total solar irradiance. Photometry of light variations in stars similar to the sun, but much younger, is providing new insights into the sun's variations in luminosity and UV radiation at previous epochs of interest to paleoclimate studies. Measurement of the sun's 11-year output variability in the ultraviolet and extreme ultraviolet still possess a challenge of great importance. All of these topics are addressed by the program on Radiative Inputs of the Sun to Earth (RISE). RISE is a 5-year program of observations, data analysis, and theory, that has been defined at two workshops held in Boulder, Colorado in November 1987, and in Tucson, Arizona in October 1989. These meetings involved about 60 solar and atmospheric physicists, and stellar astronomers. A proceedings of the 1987 workshop was issued in early 1988. A substantial component of the program, consisting of ground-based observations, data analysis, and theory, is directed at the National Science Foundation (NSF) and the program is seeking a FY-92 funding start at the NSF. RISE also makes recommendations on measurements required from NASA and NOAA satellites.

Foukal, Peter V.

Cryogenic absolute radiometers as laboratory irradiance standards, remote sensing detectors, and pyroheliometers

The dramatic improvement in heat diffusivity of pure Cu at liquid-He temperatures makes possible very important advances in the absolute accuracy, reproducibility, sensitivity, and time constant of cryogenic electrical substitution radiometers (ESRs), relative to conventional ESRs. The design and characterization of a table-top cryogenic ESR now available for detector calibration work to the 0.01-percent level of absolute accuracy under laser illumination is discussed. A sensitive cryogenic ESR recently delivered to the NIST for radiometric calibrations of black bodies is also described, along with the design and testing of a very fast cryogenic ESR developed for NASA remote-sensing studies of the earth's radiation budget.

Foukal, Peter V.