Stopping power of water for carbon ions with energies in the Bragg peak region.

Abstract

The stopping power of liquid water was measured for carbon ions with energies in the Bragg peak region using the inverted Doppler shift attenuation method. Among the semiempirical data, the results of this work agree best with the data recommended in the Errata and Addendum of ICRU Report No. 73, which is based on an I value of 78 eV for water. The agreement was worse when the present results were compared to the newer recommendation of the ICRU published in ICRU Report No. 90. The srim code seems to slightly overestimate the stopping power of water for carbon ions above 3 MeV. A semiexperimental stopping power of water for α particles was derived from the present results using the theoretical ratio between the stopping powers of water for carbon ions and α particles computed by means of the casp code. These values agree well with the experimental data for α particles within the uncertainties.