Proton stopping cross sections of liquid water

Abstract

The proton stopping cross section of liquid water for the energy range from 40 keV to 10 MeV is calculated by applying the modified local-plasma model and employing a simple model of liquid water. The calculated stopping cross section of liquid water is about 5.6% to 14% lower than the calculated vapor-state results for the range of 80 to 500 keV and is about 8.5% to. 13.4% lower than measured vapor-state results. The present results agree well with the measurements for ice crystals. The mechanism of this physical-state effect is also presented.

A dielectric response study of the electronic stopping power of liquid water for energetic protons and a newI-value for water

“…However, the optical limit in both studies is constructed based on a parameterization of the old reflectance data of Heller et al (1974). The calculations of Xu et al (1985) are based on a modified local-plasma-approximation model. The data of Wenzel and Whaling (1952) and Bauer et al (1998) are based on experimental measurements on D 2 O-ice and H 2 O-ice, respectively, with reported uncertainties at ~5%.…”

Comparisons of Calculations with PARTRAC and NOREC: Transport of Electrons in Liquid Water

“…ref. (10) and discussion therein], and yields of hydrated electrons produced by high-energy electrons (11). As described below, these sources were used to help construct inverse mean free paths for liquid water, as were the much more extensive data for water vapor and ice.…”

“…However, in atomic units, the two quantities are identical. The integration limits k min and k max are given by (10) Exchange is considered to be similar to NOREC (see above) in the sense of a semi-empirical scheme based on the Mott formula and described in detail elsewhere (4,15). The exchange corrected differential inverse mean free path for a subshell j with binding energy E j is given by (11) The energy transfer ranges from E min = E j to E max = (T + E j )/2.…”

Proton inelastic mean free path in a group of bioorganic compounds and water in 0.05–10 MeV range – Including higher-order corrections

“…The use of this theory presents the advantages of automatically including many-body effects and of accounting for the shell corrections in a self-consistent way in the evaluation of the SP at low energies, where the limitations of Bethe's stopping theory appear [9]. In the framework of dielectric response theory, a few works [9][10][11][12] have been made to evaluate the SPs for energetic protons penetrating into organic compounds, whereas the SPs of water for protons have also been studied particularly [10,[13][14][15][16][17][18] by reason of high abundance of liquid water in biological cells. Recently, with the use of different theoretical methods several groups [14,19,20] have investigated in detail the inelastic MFP calculations of low-energy protons in water for application purpose of these MFPs in proton track structure analysis in research on radiation effects.…”