The current web calculator for electronic stopping powers exploits a) the "SRIM Module.exe" included in SRIM 2013 code (SRIM Tutorials) - whose maximum available energy is 10 GeV/amu - and b) the energy-loss equation (i.e., Eq. (2.18) in Sect. 2.1.1 of [Leroy and Rancoita (2016)]) as discussed here. The overall approach is referred to as SR-treatment framework.
Output table includes the restricted energy loss in units of Mev cm2/g (i.e., the mass electronic stopping power).
The lower energy limit is 1 eV
W0 is set to be larger than five times the ionization energy of the absorber.
User can select the target as gas only for elemental gas targets: H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn.
To be remarked about W0
To a first approximation, W0 can be estimated from the electron energies whose corresponding total ranges allow electrons to be fully absorbed inside the medium, i.e., such energies cannot exceed that corresponding to the maximum pathlength inside the device. For electron energies where the radiation energy-loss is not a significant part of the energy-loss process, the practical ranges of electrons in units of g/cm2 are almost independent of the atomic mass-number of traversed absorber (e.g., see Equation (1-21) in Section 1-10 of [Price (1964)] and discussion in Sect. 2.3.2 of [Leroy and Rancoita (2016)]). An example of practical range in g/cm2 of electrons is shown in Figure 9 in this webpage). The curve is obtained using Eq. (2.134) in Sect. 2.3.2 of [Leroy and Rancoita (2016)] (see also, Eq. (1-18) in Sect. 1-10 of [Price (1964)]). Furthermore, values of the CSDA ranges of electrons in materials can be obtained from ESTAR database at NIST. Practical ranges and CSDA ranges of electrons may be employed to roughly estimate the values of W0 for microelectronic devices or semiconductor detectors.
In the present dose evaluation, it is assumed that the current effective maximum detectable energy (W0) is correctly accounting for delta rays energy deposition (see Sect. 18.104.22.168 of Leroy and Rancoita (2016)).
For few compounds belonging to the ICRU list the parameters employed for the energy loss formula (including those for the densiity effect) are reported in Table II of Sternheimer et al. (1984).