Although many of the results of XSTAR v.2 calculations are similar to those described in KM82, we present as background some results of simple models which illustrate the behavior of photoionized gas and which disply some of the adopted atomic rates and cross sections. All of the results presented in this and the next section are for optically thin models; we defer a discussion of radiation transfer effects to a later paper.

- Atomic Rates and Cross Sections
- Ionization Balance
- Heating and cooling rates
- Thermal Balance Calculation

Tim Kallman 2014-06-30