pub fn collision_step(
particle: &mut ChargedParticle,
params: &CoulombCollisionParams,
dt_s: f64,
rng_state: &mut u64,
) -> FusionResult<()>Expand description
Apply Coulomb collision Monte Carlo kick to a single particle.
Uses Langevin approach: drag (slowing-down) + stochastic pitch-angle scattering and energy diffusion over timestep dt_s.