Calculated differential equilibrium numbers of fast particles (N_i; solid lines) for the differential injection rate of primary protons given by s = 2 and E_min = 100 keV (dQ_p / dt; dotted lines). Also shown are the differential production rates of secondary knock-on electrons (dQ_e,s / dt; dashed lines). a) Λ = 10²¹ cm^-2; b) Λ = 10²⁴ cm^-2. The H density in the nonthermal X-ray production region is n_H = 10⁴ cm^-3. The calculations are normalized to a total power of 1 erg s^-1 injected by the primary LECR protons in this region.