Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-14T06:25:17.447Z Has data issue: false hasContentIssue false

Radiation Shielding Analysis for Various Materials in the Extreme Jovian Environment

Published online by Cambridge University Press:  01 February 2011

William Atwell*
Affiliation:
william.atwell@boeing.com, The Boeing Company13100 Space Center Blvd., Mail Code: HB 2-30, Houston, TX, 77059-3556, United States
Get access

Abstract

Earlier particle experiments in the 1970s on Pioneer-10 and -11 and Voyager-1 and -2 provided Jupiter flyby particle data, which were used by Divine and Garrett to develop the first Jupiter trapped radiation environment model. This model was used to establish a baseline radiation effects design limit for the Galileo onboard electronics. Recently, Garrett et al. have developed an updated Galileo Interim Radiation Environment (GIRE) model based on Galileo electron data. In this paper, the GIRE model was utilized to generate trapped proton and electron spectra as a function of Rj (Rj = radius of Jupiter = ∼71,400 km). Using these spectra and a high-energy particle transport codes (MCNPX and HZETRN), radiation exposures and dose effects for a variety of shielding materials (Al, polyethylene [PE], and Ta plus several other elemental materials for “Graded-Z” portion of the paper) and thicknesses are presented for the Icy Moon, Europa, Ganymede, and Callisto for several orbital inclinations. In addition, an in-depth discussion and absorbed dose calculations are presented for “Graded-Z” materials and several computer codes were utilized for comparison purposes. We find overall there is generally quite good agreement between the various computer codes utilized in the study: MCNPX (Monte Carlo) vs. HZETRN (deterministic) for slab shielding and the comparison of “Graded-Z” shielding using the CEPXS, NOVICE, and NASA JPL codes. Finally, we conclude that the merits of using “Graded-Z” materials that include PE, due to cost and weight, should aid future Jupiter mission planners and spacecraft designers.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Williams, D. J., McEntire, R. W., Jaskulek, S., and Wilken, B., The Galileo energetic particle detector, Space Sci. Rev. 60(1-4), 385412 (1992).Google Scholar
2. Garrett, H. B., Jun, I., Ratliff, J. M., Evans, R. W., Clough, G. A., Galileo interim radiation electron model GIRE, JPL Publication 03-006 (2003).Google Scholar
3. Divine, N. and Garrett, H. Charged particle distributions in Jupiter's magnetosphere. J. Geophys. Res. 88(A9), 68896903 (1983).Google Scholar
4. Ilwain, C. E. Mc, Coordinates for mapping the distribution of magnetically trapped particles, J. Geophys. Res. 66, 3681 (1961).Google Scholar
5. Waters, L. S.. (Editor). MCNPX User's Manual, Version 2.4.0. LA-CP-02-408, Los Alamos National Laboratory, Los Alamos, NM (2002).Google Scholar
6. Wilson, J.W., Chun, S.Y., Badavi, F.F., Townsend, L.W., and Lamkin, S.L., HZETRN: A Heavy Ion/Nucleon Transport Code for Space Radiations. NASA TP-3146, NASA Langley Research Center, Hampton, VA, 1991.Google Scholar
7. Lorence, L. J., CEPXS/ONELD Version 2: A discrete ordinates code package for general one-dimensional coupled electron-photon transport, IEEE. Transact. Nucl. Science, Vol. 39, No. 4, p. 1031, 1992.Google Scholar
8. Lorence, L J, et al., Physics guide to CEPX; A multigroup coupled electron-photon cross-section generating code. Sandia National Laboratories Report, SAND-1989, 1989 Google Scholar
9. Jordan, Tom, Experimental and Mathematical Physics Consultants, Gaithersburg, MD 20885, NOVICE code.Google Scholar