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Arxiv: Probing the relationship between early star formation and CO in the dwarf irregular galaxy WLM with JWST Published: 4/18/2024 10:50:09 PM Updated: 4/18/2024 10:50:09 PM

Paper abstract: Wolf-Lundmark-Melotte (WLM) is a Local Group dwarf irregular (dIrr) galaxywith a metallicity 13% of solar. At 1 Mpc, the relative isolation of WLMprovides a unique opportunity to investigate the internal mechanisms of starformation at low metallicities. The earliest stages of star formation in largerspirals occur in embedded clusters within molecular clouds, but dIrrs lack thedust, heavy metals, and organized structure of spirals believed necessary tocollapse the molecular clouds into stars. Despite actively forming stars, theearly stages of star formation in dIrrs is not well understood. We examine therelationship between early star formation and molecular clouds at lowmetallicities. We utilize ALMA-detected CO cores, \textit{JWST} near-infrared(NIR) images (F090W, F150W, F250M, and F430M), and \textit{GALEX}far-ultraviolet (FUV) images of WLM to trace molecular clouds, early starformation, and longer star formation timescales respectively. We compare clumpsof NIR-bright sources (referred to as objects) categorized into three typesbased on their proximity to FUV sources and CO cores. We find objects,independent of their location, have similar colors and magnitudes and nodiscernible difference in temperature. However, we find that objects near COhave higher masses than objects away from CO, independent of proximity to FUV.Additionally, objects near CO are coincident with Spitzer 8 \mum sources at ahigher frequency than objects elsewhere in WLM. This suggests objects near COmay be embedded star clusters at an earlier stage of star formation, butaccurate age estimates for all objects are required for confirmation.