Figure 5
From: Differentiating multi-MeV, multi-ion spectra with CR-39 solid-state nuclear track detectors
Most probable pit diameter μ (blue) and normalized Langau width σ = σL + ηL (red) for carbon ions versus ion energy. Data from the ion accelerator calibration are plotted as squares. Data from the TP analysis are plotted as dots marking the width of histograms from single microscope images. The larger circles plot the average width, the error bars denote the variance of the data. The continuous blue line is the calibration curve discussed in Fig. 3. The scaling of the relative width of the Langau distribution is non-monotonic and different from the scaling of the most probable pit diameter. The width of the Langau distribution was divided by μ to show the relative scaling in a unitless quantity. In black we plot scaled results of a TRIM simulation for the vacancy production in the first µm of CR-39, which exhibits a similar scaling. The gray vertical lines mark the initial energy of C ions corresponding to a 1, 2, or 3 µm stopping range, which is close to the etched pit depth. Near the end of the ion range, the distribution broadens and can no longer be described by a Langau distribution.
