Accession Number : AD0716801

Title :   Atmospheric Transport of X-Rays.

Descriptive Note : Final rept.,

Corporate Author : GULF ENERGY AND ENVIRONMENTAL SYSTEMS INC SAN DIEGO CALIF

Personal Author(s) : Harris,R. J. , Jr. ; Nowak,M. J. ; Lonergan,J. A. ; Wondra,J. P. ; Willoughby,D. F.

Report Date : 16 JUN 1970

Pagination or Media Count : 156

Abstract : Due to the lack of measured data for checking calculational results, an experimental program was initiated at Gulf General Atomic (GGA) for studying the atmospheric transport properties of X-rays by using liquid nitrogen to simulate air. Measurements of the photon spectrum and angular distribution were made as a function of source-detector separation distance in an 'infinite' medium of liquid nitrogen provided by a large cryogenic dewar. Radioactive isotopes of 241Am, 141Ce, and 203Hg were used as sources of approximately monoenergetic photons with energies of 60 keV, 145 keV and 279 keV, respectively. A 20 cc cm Ge(Li) detector was used to measure photon spectra for energies from approximately 20 keV to the source energy. Measurements were made for source detector distances of 1-15 mfp for each source energy. Transport calculations were made for comparison with the measurements using the PHOTRAN Monte Carlo code and the 1DF discrete ordinates code. (Author)

Descriptors :   (*ATMOSPHERE MODELS, X RAYS), (*X RAYS, TRANSPORT PROPERTIES), PHOTONS, SPECTRUM ANALYZERS, INTEGRALS, NUMERICAL INTEGRATION, CURVE FITTING, MONTE CARLO METHOD, STATISTICAL DISTRIBUTIONS, COMPUTER PROGRAMMING, RADIOACTIVE ISOTOPES

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE