Fast neutron flux spectrum aboard Mars Odyssey during cruise

W. C. Feldman, T. H. Prettyman, R. L. Tokar, William V. Boynton, R. C. Byrd, K. R. Fuller, O. Gasnault, J. L. Longmire, R. H. Olsher, S. A. Storms, G. W. Thornton

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

[1] The energy spectrum of fast neutrons generated by interactions between galactic cosmic rays and the Mars Odyssey spacecraft during quiet interplanetary conditions is determined. It is given by Φn(En) = (0.071 ± 0.0044) En-(0.28±0.055) cm -2 s-1 MeV-1 for energies between 0.7 and 6 MeV. The estimated ratio of this component of spacecraft neutron background to the Martian leakage flux in Mars orbit is expected to amount to between 0.30 and 0.34. This fraction is sufficiently small so that the total background in orbit about Mars is expected to be dominated by Martian leakage neutrons reprocessed by the spacecraft. Nevertheless, the measured asymmetry properties of the Odyssey Neutron Spectrometer response function should allow separation of foreground and background neutron fluxes when in Mars orbit. The fast neutron flux between 0.7 and 6 MeV should only contribute 0.40 Roentgen Equivalent Man (rem) per year to the total radiation dose aboard a Mars Odyssey class spacecraft at solar maximum.

Original languageEnglish (US)
JournalJournal of Geophysical Research: Space Physics
Volume107
Issue numberA6
DOIs
StatePublished - 2002

Fingerprint

Neutron flux
fast neutrons
flux (rate)
mars
Spacecraft
Mars
spacecraft
Neutrons
Orbits
orbits
Neutron spectrometers
leakage
Cosmic rays
neutrons
neutron spectrometers
Dosimetry
cosmic ray
energy
Fluxes
asymmetry

Keywords

  • Energy spectrum
  • Fast neutrons
  • Spacecraft background

ASJC Scopus subject areas

  • Geophysics
  • Space and Planetary Science

Cite this

Feldman, W. C., Prettyman, T. H., Tokar, R. L., Boynton, W. V., Byrd, R. C., Fuller, K. R., ... Thornton, G. W. (2002). Fast neutron flux spectrum aboard Mars Odyssey during cruise. Journal of Geophysical Research: Space Physics, 107(A6). https://doi.org/10.1029/2001JA000295

Fast neutron flux spectrum aboard Mars Odyssey during cruise. / Feldman, W. C.; Prettyman, T. H.; Tokar, R. L.; Boynton, William V.; Byrd, R. C.; Fuller, K. R.; Gasnault, O.; Longmire, J. L.; Olsher, R. H.; Storms, S. A.; Thornton, G. W.

In: Journal of Geophysical Research: Space Physics, Vol. 107, No. A6, 2002.

Research output: Contribution to journalArticle

Feldman, WC, Prettyman, TH, Tokar, RL, Boynton, WV, Byrd, RC, Fuller, KR, Gasnault, O, Longmire, JL, Olsher, RH, Storms, SA & Thornton, GW 2002, 'Fast neutron flux spectrum aboard Mars Odyssey during cruise', Journal of Geophysical Research: Space Physics, vol. 107, no. A6. https://doi.org/10.1029/2001JA000295
Feldman, W. C. ; Prettyman, T. H. ; Tokar, R. L. ; Boynton, William V. ; Byrd, R. C. ; Fuller, K. R. ; Gasnault, O. ; Longmire, J. L. ; Olsher, R. H. ; Storms, S. A. ; Thornton, G. W. / Fast neutron flux spectrum aboard Mars Odyssey during cruise. In: Journal of Geophysical Research: Space Physics. 2002 ; Vol. 107, No. A6.
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