Doke, T., Hayashi, T. and Borak, T. B. Comparisons of LET Distributions Measured in Low-Earth Orbit Using Tissue-Equivalent Proportional Counters and the Position-Sensitive Silicon-Detector Telescope (RRMD-III). Radiat. Res. 156, 310–317 (2001).
Determinations of the LET distribution, ϕ(L), of charged particles within a spacecraft in low-Earth orbit have been made. One method used a cylindrical tissue-equivalent proportional counter (TEPC), with the assumption that for each measured event, lineal energy, y, is equal to LET and thus ϕ(L) = ϕ(y). The other was based on the direct measurement of LETs for individual particles using a charged-particle telescope consisting of position-sensitive silicon detectors called RRMD-III. There were differences of up to a factor of 10 between estimates of ϕ(L) using the two methods on the same mission. This caused estimates of quality factor to vary by a factor of two between the two methods.