Module stopping 

Electronic stopping of ions in matter, from published formulas only.

Conventions

• The stopping quantity returned by every model is the stopping cross section per target atom, S_e = (1/N) (-dE/dx), in J m² per atom (SI). to_ev_1e15_cm2 converts to the customary eV·10⁻¹⁵ cm²/atom.
• Energies are the ion’s kinetic energy in the laboratory frame, in eV (_ev suffix at the API boundary, as in crate::units).
• Reduced quantities (ε, ρ) are the Lindhard-Scharff ones, defined in lindhard_scharff.
• Every model is a pure function of (ion, target Z, energy): no RNG, no state, so results are bitwise reproducible across threads.

Validity ranges per model are in docs/stopping-models.md and are exposed at run time by ElectronicStopping::validity.

No tabulated SRIM or ICRU data enters this module. Terms whose published coefficients are only available from such tables are omitted, and the omission is listed in docs/stopping-models.md.

Modules

bethe

Bethe-Bloch electronic stopping (relativistic) with Bloch and optional user-supplied shell/density corrections, and a named effective-charge model.

bragg

Bragg additivity for compounds and mixtures.

correction

Per-pair multiplicative correction of an electronic-stopping model, fitted to measured points, with a bootstrap uncertainty and held-out residuals.

dataset

Stopping datasets: measured S_e points with a citation on every point, and the comparison of an ElectronicStopping model against them.

lindhard_scharff

Lindhard-Scharff electronic stopping.

mix

Equipartition mix of Lindhard-Scharff (nonlocal) and Oen-Robinson (local).

none

No electronic stopping: the nuclear-only limit.

oen_robinson

Oen-Robinson local (impact-parameter dependent) electronic energy loss.

straggling

Electronic energy-loss straggling.

table

User-supplied S_e(E) tables, loaded from TOML, with mandatory provenance.

Structs

Ion

A projectile: atomic number and mass.

ValidityRange

Advisory energy range over which a model is meant to be used, eV.

Enums

StoppingError

Errors from stopping models, tables and Bragg sums.

Traits

ElectronicStopping

An electronic stopping model.

Functions

bohr_velocity

Bohr velocity v0 = α c, m/s.

from_ev_1e15_cm2

Convert eV·10⁻¹⁵ cm² per atom to J m² per atom.

speed_nonrel

Ion speed from kinetic energy, non-relativistic sqrt(2E/M), m/s.

to_ev_1e15_cm2

Convert J m² per atom to eV·10⁻¹⁵ cm² per atom (1e-15 cm² = 1e-19 m²).