a guideline, a more general suppression formula is then determined by fitting to suppression results from extensive detailed collisional-radiative calculations [@summersRAL] for a wide range of ions at several densities and (high) temperatures. Additional modifications are then introduced to account for low temperature DR.

The outline of the rest of the paper is as follows: in the next section we describe the DR suppression model we use; we then apply this suppression to the zero-density DR data, and use the resultant density-dependent DR data in Cloudy to determine the ionization distribution produced under photoionized and collisional ionization equilibrium at low and moderate densities.

Generalized Density Suppression Model {#Sec:Suppress}
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We use the following approach, detailed more fully in the subsections below. First, the high-temperature collisional-radiative modeling results of @badnell for DR suppression in are parameterized by a pseudo-Voigt profile to study the qualitative behavior of suppression as a function of density and temperature. Next, this formulation is then used as a guideline for developing a more comprehensive suppression formula which is obtained by fitting to collisional radiative data for various isoelectronic sequences, ionic charges, densities, and temperatures [@summersRAL]. Lastly, the suppression formulation is extended to low-temperatures according to the nature 