Caltech/IPAC Seminar

Understanding how galaxies transition from turbulent systems to mature disks requires spatially resolved measurements of their star formation, interstellar medium, and dynamical structure. I will discuss results from the MSA-3D survey, which uses JWST/NIRSpec MSA with a slit stepping strategy to produce kpc-resolution integral field spectroscopy for main-sequence star-forming galaxies at z=1-3, spanning the cosmic noon and the epoch of thin disk emergence. 

Our recent results on spatially resolved dust attenuation reveal substantial diversity in radial attenuation profiles and thus ISM distribution of individual galaxies, suggesting variations in their evolutionary pathways. In addition, while attenuation generally increases with stellar mass, spatial variations in dust distribution can bias attenuation and star-formation rates measured from fixed apertures. However, we find that sample-averaged star-formation rates remain consistent with the star-forming main-sequence and a small scatter. 

I will place these results in the broader context revealed by MSA-3D: ordered rotation and negative metallicity gradients indicate that dynamically settled disks are already established in some z~1 galaxies. Spatially resolved BPT diagnostics show harder radiation fields and lower metallicities relative to z~0. We find that ~16% of the sample exhibits weak AGN, shocks, or outflows, tracing the feedback processes which regulate their evolution. These results together provide a comprehensive picture of the emergence of the modern Hubble sequence, linking kinematics, metallicity, dust and interstellar medium, and SFR profile diversity to the physical processes (e.g. inside-out growth, quenching) that drive this transformation.