Ryota Ikeda (NAOJ/SOKENDAI)
From kpc to sub-kpc scales census of distant star-forming galaxies using ALMA and JWST

Cold gas accretion and stellar/AGN feedbacks create radial variations in the physical properties of galaxies. Therefore, spatially-resolved information on the interstellar medium in distant galaxies is crucial for understanding galaxy evolution. I will introduce two ongoing ALMA projects (CRISTAL and FOSSILS), which aim to resolve distant star-forming galaxies at kpc to sub-kpc scales. I will particularly highlight our study of the extended [CII]158μm line emission (the so-called "[CII] halo"), which we suggest partially traces an extended atomic gas component at large radii (Ikeda et al. 2025). Additionally, I will present ongoing work on sub-kpc imaging of submillimeter galaxies (SMGs), including a combined analysis of stellar dust distributions in three SMGs (Ikeda et al., in prep). Our findings suggest that multiple pathways exist for triggering intense starbursts in the luminous SMG population.