High-redshift starbursts provide unique laboratories to investigate the ISM and star formation under extreme, gas-rich conditions compared to their low-redshift analogs. I will present spatially resolved observations of three morphologically distinct starbursts at z ~ 1.5 with ALMA and JWST NIRCam/MIRI. The combination of molecular line and dust continuum data from ALMA with multi-band rest-frame optical–mid-IR imaging from JWST allows us to probe the gas content, kinematics, and obscured structures at 0.3～3 kpc scales. The three galaxies span a broad morphological and dynamical diversity, including a major merger, a minor merger, and a grand-design spiral starburst. While differing in their triggering mechanisms, all systems reveal centrally concentrated, dusty rotating disks with enhanced star formation in their cores, suggestive of rapid bulge growth. The latter two starbursts provide compelling evidence that secular processes or minor mergers can be effective enough in driving intense star formation at cosmic noon. Furthermore, spatially resolved analysis of dust, gas, and PAH emission reveals suppressed PAH features in the central starbursting regions relative to spiral arms in the grand-design starburst. Specifically in the major merger system, ALMA detects signatures of extreme processes such as molecular outflows and radio jets, likely driven by the intense interaction. Together, these results highlight both diversity and commonality of high-z starbursts: while starburst triggers and features vary, their outcomes converge toward compact, dusty, star-forming disks that may contribute to rapid bulge growth. These findings demonstrate the importance of multi-wavelength, spatially resolved studies in constraining how massive galaxies assemble during the peak epoch of cosmic star formation.
Local contact & organiation: Emanuele DADDI
DAp