Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

Citation
Fa. Cucinotta et al., Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO, RADIAT MEAS, 32(3), 2000, pp. 181-191
Citations number
50
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
RADIATION MEASUREMENTS
ISSN journal
1350-4487 → ACNP
Volume
32
Issue
3
Year of publication
2000
Pages
181 - 191
Database
ISI
SICI code
1350-4487(200006)32:3<181:AOMRFP>2.0.ZU;2-1
Abstract
We compare models of radiation transport and biological response to physica l and biological dosimetry results from astronauts on the Mir space station . Transport models are shown to be in good agreement with physical measurem ents and indicate that the ratio of equivalent dose from the Galactic Cosmi c Rays (GCR) to protons is about 3/2:1 and that this ratio will increase fo r exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cel ls; a track-structure model and the linear-quadratic model with linear ener gy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement wit h data for aberrations in lymphocytes of Mir crew members: however there ar e differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major differe nce in the models is the increased effectiveness predicted by the track mod el for low charge and energy ions with LET near 10 keV/mu m. The results of our calculations indicate that aluminum shielding, although providing impo rtant mitigation of the effects of trapped radiation, provides no protectiv e effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measur e until about 100 g/cm(2) of material is used. Published by Elsevier Scienc e Ltd.