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Title: Simulation of HEAO 3 background

Journal Article · · AIP Conference Proceedings
DOI:https://doi.org/10.1063/1.54027· OSTI ID:21172433
 [1];  [2]; ;  [3]
  1. George Mason University, Fairfax, Virginia (United States)
  2. USRA, Washington, District of Columbia (United States)
  3. Naval Research Laboratory, Washington, District of Columbia (United States)

A Monte Carlo technique for modeling background in space-based gamma-ray telescopes has been developed. The major background components included in this modeling technique are the diffuse cosmic gamma-ray flux, the Earth's atmospheric flux, and decay of nuclei produced by spallation of cosmic rays, trapped protons and their secondaries, the decay of nuclei produced by neutron capture, and the de-excitation of excited states produced by inelastic scattering of neutrons. The method for calculating the nuclear activation and decay component of the background combines the low Earth orbit proton and neutron spectra, the spallation cross sections from Alice91, nuclear decay data from the National Nuclear Data Center's (NNDC) Evaluated Nuclear Structure Data File (ENSDF) database, and three-dimensional gamma-ray and beta transport with Electron Gamma-ray Shower version 4 (EGS4) using MORSE combinatorial geometry. This Monte Carlo code handles the following decay types: electron capture, {beta}{sup -}, {beta}{sup +}, meta-stable isotope and short lived intermediate states, and isotopes that have branchings to both {beta}{sup -} and {beta}{sup +}. Actual background from the HEAO 3 space instrument are used to validate the code.

OSTI ID:
21172433
Journal Information:
AIP Conference Proceedings, Vol. 410, Issue 1; Conference: 4. Compton symposium, Williamsburg, VA (United States), 27-30 Apr 1997; Other Information: DOI: 10.1063/1.54027; (c) 1997 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
Country of Publication:
United States
Language:
English