Pox 186 is an exceptionally small dwarf starburst galaxy hosting a stellar mass of ∼105 Me. Undetected in H I (M < 106 Me) from deep 21 cm observations and with an [O III]/[O II] (5007/3727) ratio of 18.3 ± 0.11, Pox 186 is a promising candidate Lyman continuum emitter. It may be a possible analog of low-mass reionization-era galaxies. We present a spatially resolved kinematic study of Pox 186 and identify two distinct ionized gas components: a broad one with σ > 400 km s−1 and a narrow one with σ < 30 km s−1. We find strikingly different morphologies between the two components and direct evidence of outflows as seen in the high-velocity gas. Possible physical mechanisms driving the creation of high-velocity gas seen in [O III] are discussed, from outflow geometry to turbulent mixing between a hot (106 K) star-cluster wind and cooler (104 K) gas clouds. We find a modest mass-outflow rate of 0.022 Me yr−1 with a small mass-loading factor of 0.5, consistent with other low-mass galaxies. Finally, we compare the mass-loading factor of Pox 186 with extrapolations from numerical simulations and discuss possible reasons for the apparent discrepancy between them.
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