Photoionization Models of NGC 346

We present spherically symmetric and plane parallel photoionization models ofNGC 346, an HII region in the Small Magellanic Cloud. The models are based onCLOUDY and on the observations of Peimbert, Peimbert, & Ruiz (2000). We findthat approximately 45% of the H ionization photons escape from the HII regionproviding an important ionizing source for the low density interstellar mediumof the SMC. The predicted I(4363)/I(5007) value is smaller than that observed,probably implying that there is an additional source of energy not taken intoaccount by the models. From the ionization structure of the best model and theobserved line intensities we determine the abundances of N, Ne, S, Ar, and Ferelative to O.Comment: 23 pages, 2 figures, Accepted for publication in Ap