The effects of stimulated recombination

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 $\varepsilon^{-1}$ 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.

**Figure 1:** figure 1a
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**Figure 1:** figure 1b
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**Figure 2:** figure 2
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**Figure 3:** figure 3a
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**Figure 3:** figure 3b
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**Figure 4:** figure 4a
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**Figure 4:** figure 4b
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**Figure 5:** figure 5a
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**Figure 5:** figure 5b
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**Figure 6:** figure 6a
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**Figure 6:** figure 6b
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**Figure 7:** figure 7a
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**Figure 7:** figure 7b
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**Figure 8:** figure 8a
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**Figure 8:** figure 8b
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**Figure 9:** figure 9a
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**Figure 9:** figure 9b
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