Comparison of FWHM

A comparison has been made with low energy data ($0.3\; \le T/A\; \le 2.5$ MeV/A) in very thin absorbers (1,7 $\mu$ m, 0.4 $\mu$ m). Data are taken from the tables in [] for energy loss of O ions in Al, and the results are reported in table . The quoted experimental error for these data is $1$ statistical + $5$ systematic for 417 $\mu$ g $cm-2$ data and $2$ statistical + $10$ systematic for 110 $\mu$ g $cm-2$ data.

Plots of energy deposition distributions of 1.4 MeV/A lead and helium ions in gases can be found in []. From these we have measured the FWHM and compared them with the ones given by the MonteCarlo. The results can be seen in table and . It should be noted that the absorber thickness of, for example, Ar compares with that of the preceding case (0.2 cm Ar = 356 $\mu$ g $cm-2$ and 1.2 cm Ar = 2136 $\mu$ g $cm-2$ ).

Similar comparison has been made for C ions of energies 17.1 and 39.4 MeV in isobuthane [] and the agreement between data and GEANT for FWHM is within 30%.

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