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He ions in Ar (energies in keV)
MonteCarlo data
t (cm) ∆E FWHM FWHM
0.5 444 38 ∼40
1.0 913 53 ∼60
2.0 1940 78 ∼80
Table 1.13: Comparison of the measured and calculated and FWHM for 1.4 MeV/A He ions in gas.
3 Comparison with data
3.1 Mean energy loss and range
A test has been made against the distributions reported in [94] for He ions at 1 and 10 MeV/A and for O
and Pb ions at 1, 10 and 100 MeV/A in carbon and the results were found to be correct within 5% both for
the energy loss and the range.
Figure 44: Stopping powers in Lead
Another comparison has been made with the tables of [95] for 10 MeV/A ions in lead, with the results
shown in table 2. Another comparison with the same tables is shown in Figs. 43 and 44.
A comparison with the tables in [83, 93] for T/A < 1 MeV/A gives an error on (dE/dx) ≤ 10 − 20%.
3.2 Comparison of FWHM
A comparison has been made with low energy data (0.3 ≤ T/A ≤ 2.5 MeV/A) in very thin absorbers (1,7
µm, 0.4 µm). Data are taken from the tables in [96] for energy loss of O ions in Al, and the results are
reported in table 2. The quoted experimental error for these data is 1% statistical + 5% systematic for 417
µg cm −2 data and 2% statistical + 10% systematic for 110 µg cm −2 data.
Plots of energy deposition distributions of 1.4 MeV/A lead and helium ions in gases can be found in [97].
From these we have measured the FWHM and compared them with the ones given by the MonteCarlo. The
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