Abstract
Nearby metal-poor starburst dwarf galaxies present a unique opportunity to probe the physics of high-density star formation with a detail and sensitivity unmatched by any observation of the high-z Universe. These chemically unevolved galaxies also offer insight into the synthesis, dispersal, and ejection of metals in galaxies, from the inflows of minimally processed material to the metal-enriched outflows driven by intense star formation events. In this talk we present our results from a chemodynamical study of the nearby (D~20 Mpc) gas-rich starbusting dwarf galaxy CGCG 007-025. We combine HST/WFC3 imaging, VLT/MUSE integral field spectroscopy and Magellan/MIKE echelle spectra to characterise the properties of the star-forming gas, from its metal content to its kinematics. The star formation rate surface density presents a clumpy distribution, with the brightest knot hosting a 5 Myr young, Wolf-Rayet population. The electronic temperature and density of the gas are normally distributed, with values typically found in SF regions. However, in the brightest SF complex in the galaxy the electronic density triples, where the extinction coefficient also increases. A superposition of a narrow (sigma~50 km/s), intermediate (150 km/s) and broad (1000 km/s) kinematic components are needed to model the emission line profiles in the brightest SF region, suggesting the presence of energetic outflows from massive stars. The galaxy presents a perfect anti-correlation between the star formation rate surface density and the oxygen abundance, whereas the Nitrogen-to-Oxygen ratio remains constant across the entire galaxy. Our findings are compatible with a scenario of gas accretion due to the interaction. This metal-poor starburst constitutes a perfect local analogue to investigate high density star formation in low-mass galaxy haloes, and allows us to study it with unprecedented detail and sensitivity.
