Stellar Populations and Molecular Gas Composition in the Low-Metallicity Environment of WLM

Abstract

We investigate the stellar populations and molecular gas properties of a star-forming region within the dwarf irregular (dIrr) galaxy WLM. Low-metallicity dIrrs like WLM offer a valuable window into star formation in environments that are unlike those of larger, metal-rich galaxies such as the Milky Way. In these conditions, carbon monoxide (CO), typically used to trace molecular clouds, is more easily photodissociated by ultraviolet (UV) radiation, leading to a larger fraction of CO-dark molecular gas, where H$_2$ exists without detectable CO emission, or CO-dark gas in the form of cold HI. Understanding the molecular gas content and the stellar populations in these star-forming regions provides important information about the role of CO-bright and CO-dark gas in forming stars.