Interpretation of Various Radiation Backgrounds Observed in the Gamma-Ray Spectrometer Experiments Carried on the Apollo Missions and Implications for Diffuse Gamma-Ray Measurements

C S Dyer; J I Trombka; A E Metzger; S M Seltzer; M J Bielefeld; L G Evans

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NASA NTRS · 19760043886

Interpretation of Various Radiation Backgrounds Observed in the Gamma-Ray Spectrometer Experiments Carried on the Apollo Missions and Implications for Diffuse Gamma-Ray Measurements

C S Dyer·J I Trombka·A E Metzger·S M Seltzer·M J Bielefeld·L G Evans

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Abstract

Since the report of a preliminary analysis of cosmic gamma-ray measurements made during the Apollo 15 mission, an improved calculation of the spallation activation contribution has been made including the effects of short-lived spallation fragments, which can extend the correction to 15 MeV. In addition, a difference between Apollo 15 and 16 data enables an electron bremsstrahlung contribution to be calculated. A high level of activation observed in a crystal returned on Apollo 17 indicates a background contribution from secondary neutrons. These calculations and observations enable an improved extraction of spurious components and suggest important improvements for future detectors.

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C S Dyer, J I Trombka, A E Metzger, S M Seltzer, M J Bielefeld, L G Evans. 1975-01-01. Interpretation of Various Radiation Backgrounds Observed in the Gamma-Ray Spectrometer Experiments Carried on the Apollo Missions and Implications for Diffuse Gamma-Ray Measurements. https://ntrs.nasa.gov/citations/19760043886

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