So far in this section we have artificially excluded the effects of stimulated
recombination (by manually setting the rates to zero when calculating total
recombination). We illustrate the effect of relaxing this condition in figure 16,
which is the equivalent of figure 9 (recombination rates vs. density) but
with stimulated recombination included. Again the ionizing spectrum is
a
power law, which has strong flux at the lowest photon
energies. Comparison of figures 16 and 9 shows that the rates are greatly enhanced
at high densities, and this enhancement is greatest for ions with lowest
ionization potentials. This is due to the influence of the low energy photons
on the stimulated recombination rate, and a different spectral shape (e.g. a blackbody)
would produce a different distribution of recombination with charge state at high
densities.