Performance Study Of Galactic Cosmic Ray Shield Materials

In past studies, the reductions in absorbed dose and dose equivalent due to choice of material composition have been used to indicate shield effectiveness against exposure to galactic cosmic rays. However, these quantities are highly inaccurate in assessing shield effectiveness for protection against the biological effects of long-term exposure to the galactic heavy ions. A new quantity for shield performance is defined that correlates well with cell killing and cell transformation behind various shield thicknesses and materials. In addition, a relative performance index is identified that is inversely related to biological injury for different materials at a fixed shield mass and is directly related to the ratio of the fourth- and the second-order linear energy transfer (LET) moments. Wilson, John W. and Wood, J. S. and Shinn, Judy L. and Cucinotta, Francis A. and Nealy, John E. Langley Research Center NASA-TM-4444, L-17199, NAS 1.15:4444 RTOP 592-43-21-01...

The purpose of the workshop was to define requirements for the development and evaluation of high performance shield materials and designs and to develop ideas regarding approaches to radiation shielding.