Estimate of the space station shielding thickness at a USLab site using ALTEA measurements and fragmentation cross sections

In this work we presented a method to estimate a local shielding thickness of the International Space Station (USLab), expressed as equivalent of aluminum. The calculation took advantage of total and partial charge-changing cross sections, both measured experimentally and computed theoretically, to obtain the total survival fractions of ions with charge 5 <= Z <= 26 when transversing the space craft hull. The combination of these values with the measured relative abundances outside the space station provided the estimates of the internal relative abundances at several thicknesses. The results have been compared with data measured by ALTEA experiment in the USLab to find the thickness that minimizes the discrepancy between the calculated data and the measurements: the result yielded to an estimate of the shielding thickness at ALTEA site of about 5 cm of aluminum equivalent. (C) 2009 Elsevier B.V. All rights reserved.