Linear Energy Transfer Spectra and Dose Equivalents of Galactic Radiation Exposure in Space

Download or read book Linear Energy Transfer Spectra and Dose Equivalents of Galactic Radiation Exposure in Space written by Hermann J. Schaefer and published by . This book was released on 1966 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: In assessing the astronaut's exposure from galactic cosmic rays on space missions of long duration conversion of absorbed doses to dose equivalents is required. Since a large part of the dose contribution from heavy primaries is produced at Linear Energy Transfer (LET) values beyond the range for which radiobiological data are available, it seems preferable to analyze the LET distributions themselves and to compare them to standard x-rays rather than to assume arbitrary values for the Relative Biological Effectiveness(RBE). The local LET distributions in tissue are found to be extremely skewed, with a large maximum at the relativistic minimum LET. Lined up on the LET scale, they cover the very wide interval from 0.18 to 2790 kev/micron T as compared to an interval from 0.4 to 35 kev/micron T for standard x-rays. Applying the RBE formula of the RBE Committee of the ICRP and a saturation value of 10 leads to a grand mean RBE of 1.82 for the total absorbed dose of 13 millirads/24 hours from primaries. (Author).