* FLUKA uses an original transport algorithm for charged particles [Fer91a], including complete multiple Coulomb scattering treatment giving the correct lateral displacement even near a boundary (see hadron and muon transport above). * The variations with energy of the discrete event cross sections and of the continuous energy loss in each transport step are taken into account exactly. * Differences between positrons and electrons are taken into account concerning both stopping power and bremsstrahlung [Kim86]. * The bremsstrahlung differential cross sections of Seltzer and Berger [Sel85, Sel86] have been extended to include the finite value at "tip" energy, and the angular distribution of bremsstrahlung photons is sampled accurately. * The Landau-Pomeranchuk-Migdal suppression effect [Lan53, Lan53a, Mig56, Mig57] and the Ter-Mikaelyan polarisation effect in the soft part of the bremsstrahlung spectrum [Ter54] are also implemented. * Electrohadron production * Positron annihilation in flight and at rest. * Delta-ray production via Bhabha and Möller scattering.Note:the present lowest transport limit for electrons is 1 keV. Although in high-Z materials the Molière multiple scattering model becomes unreliable below 20-30 keV, a single-scattering option is available which allows to obtain satisfactory results in any material also in this low energy range. The minimum recommended energy for PRIMARY electrons is about 50 to 100 keV for low-Z materials and 100-200 keV for heavy materials, unless the single scattering algorithm is used. Single scattering transport allows to overcome most of the limitations at low energy for the heaviest materials at the price of some increase in CPU time.
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