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Introduction

In May, 1994, the Lexington conference on photoionization modeling was held in order to better understand the differences between the various codes available for solving photoionization problems. The conference was attended by approximately 8 modelers actively involved in the solution of problems involving H II regions, nova envelopes, planetary nebulae, and AGN clouds. As part of the workshop the participants were asked to run several standard problems and compare the results. These were chosen from what were thought to be representative models of H II regions, planetary nebulae, and AGN clouds. The results will appear in a book on the proceedings of the Space Telescope Institute Conference on Emission Lines. In this appendix we reproduce the comparison with the results of XSTAR 1.17 with the other models given in the conference proceedings, along with the input files needed to reproduce these results. Note that version 1.17 has added an input command 'benchmark $n$', where $n$ is an integer from 1 to 8, representing the test case in the Lexington paper. This command produces a table, similar to the 'print line_fluxes' command, but also including the mean value and dispersion of each line flux from the ensemble of model results in the Lexington paper (with the results of the current run substituted for the XSTAR results given there; columns 5 and 6), the flux from the current XSTAR run (in the appropriate units asadopted by the Lexington conference; column 7), and the number of 'sigmas' the XSTAR result differs from the mean (column 4). The last line gives the summed $\chi^2$ for all lines from the 10 codes represented in the Lexington paper. The first two entries are always zero; the XSTAR $\chi^2$ is in the 4th non-zero column (column 6).


next up previous contents
Next: Cool H II Region Up: The Lexington Benchmarks Previous: The Lexington Benchmarks   Contents
Tim Kallman 2014-09-12