Everything Every Band All at Once. I. A Global Morphology Catalog in A2744 Based on UNCOVER/MegaScience

Abstract

We present spectrally resolved structural parameter measurements of 28,274 sources from the legacy lensing field of A2744, quantifying global structures from the observed 0.7−4.8 μm and spanning rest-frame UV to near-infrared (NIR) at R ∼ 15. These measurements are made on imaging mosaics mainly from the UNCOVER/MegaScience survey, including 20 JWST NIRCam broad and medium bands. We perform single-component Sérsic fitting to these galaxies using pysersic, a Bayesian structural fitting tool, to infer their structural parameters and associated random uncertainties from the posterior distributions. Through various quality evaluation criteria, we infer robust structural parameters among >85% of the selected signal-to-noise-ratio (SNR) > 10 sources. For each galaxy with reliable sizes in at least two bands and a high-quality redshift, we fit its observed size as a function of wavelength and infer rest-frame UV, optical, and NIR sizes where applicable. By performing injection-recovery tests on simulated galaxy cutouts in selected bands, we establish that our structural parameter measurements achieve a fractional error <10%−20% above SNR > 10. With this paper, all raw structural measurements and fitted rest-frame sizes are quality flagged, cataloged, and released to the community. Finally, we demonstrate that this catalog enables the structural study of galaxies over an unprecedentedly wide parameter space of redshift (0.3 < z < 8), stellar mass (107 M⊙ < M* < 1011.5 M⊙), and rest-frame optical size (100 pc < Re < 10 kpc), after correcting for lensing magnification.