Prevalence of complex density structure in nearby metal-poor dwarf galaxies

Determine whether complex ionized-gas density structure similar to that inferred in high-redshift star-forming galaxies is common among nearby metal-poor dwarf galaxies.

Background

The paper examines whether integrated optical and far-infrared [O III] emission in nearby metal-poor dwarf galaxies can be described by a homogeneous one-zone model with a single electron temperature and density. Comparisons among [O III] optical and far-infrared lines, together with independent optical and ultraviolet density diagnostics, reveal substantial diagnostic-dependent density differences in SBS 0335−052E and Haro 11, while POX 186 and I Zw 18 show different patterns of consistency.

These results motivate the possibility that unresolved density structure—either distinct gas components or a broad underlying distribution of densities—may be common in local metal-poor galaxies and may explain analogous diagnostic discrepancies in high-redshift systems. The authors explicitly identify the prevalence of such complex structure in nearby metal-poor galaxies as unresolved.