CEERS: Forging the First Dust -- Transition from Stellar to ISM Grain Growth in the Early Universe

TL;DR

This study uses JWST data to explore how dust and metals coevolve in early galaxies, revealing a transition from stellar to grain growth dominance around a specific stellar mass, and implications for early universe galaxy properties.

Contribution

It identifies a critical stellar mass where dust production shifts from stellar sources to grain growth, supported by observational data and models.

Findings

Transition at Mstar=10^8.5 MSun from stellar to grain growth dust

Detection of stardust galaxies explains excess of UV-bright galaxies at z>10

High metallicity ratios indicate rapid metal enrichment at high redshift

Abstract

We investigate the coevolution of metals and dust for 173 galaxies at 4.0<z<11.4 observed with JWST/NIRSpec. We use the code CIGALE that integrates photometric and spectroscopic data. Our analysis reveals a critical transition at Mstar = 10^8.5 MSun, from galaxies dominated by supernovae and AGB stardust, to those dominated by grain growth. This implies a two-mode building of dust mass, supported by model predictions. The detection of stardust galaxies provides a natural and inherent explanation to the excess of UV-bright galaxies at z>10 by JWST. Besides, we observe that the metallicity of galaxies at z>8 presents a metal-to-stellar mass ratio larger than a few 10^-3, above a floor. This suggests a very fast rise of metals at high redshift, impacting the tentative detections of population III objects.