Figure 12.

(a) Comparison of a measured PHS (FOS 600 HL #bib25 keV) and calculated PHS when $\overline{\mathit{\epsilon }}(0)$ is varied by ± 10% of its estimated value. Agreement between the modeled and measured PHS is strongly affected by $\overline{\mathit{\epsilon }}(0)$, which shifts the position of the modeled PHS peak. (b) PHS calculated when $\overline{\mathit{\epsilon }}(0)$ is fixed and $\overline{\mathit{\epsilon }}(L)$ varied by ± 10%. Agreement between the modeled and measured PHS is less sensitive to changes in $\overline{\mathit{\epsilon }}(L)$, which primarily affect the upper PHS tail.