GA-NIFS: The interplay between feedback and star formation at 3 < z < 9 probed by JWST/NIRSpec IFU

Authors:
Open Access
Publisher website
Google Scholar
Abstract
The study of starburst- and active galactic nucleus (AGN)-driven feedback is fundamental for understanding the processes that shape galaxy growth, quench star formation, and drive the co-evolution of galaxies and their central black holes. We present a spatially resolved study of six galaxies at 3 < z < 9, including starburst- and AGN-dominated systems, observed with the JWST/NIRSpec Integral Field Unit in low- ( R ∼ 100) and high-resolution ( R ∼ 2700) mode. Previous analyses of R ∼ 2700 data revealed ionized outflows in all these galaxies. We explored possible links between outflows and stellar population properties to assess the mechanisms driving galaxy evolution at early epochs. We derived stellar masses and star formation histories (SFHs) using the spectral energy distribution fitting code Prospector , applied to both single spaxels and spatially integrated spectra, exploring parametric and non-parametric SFHs. We find that unresolved stellar mass measurements are systematically underestimated, with discrepancies increasing towards higher sSFRs (up to ∼0.75 dex), consistent with the so-called outshining effect. Combining the spatially resolved stellar population analysis with the outflow properties, we find that the most massive galaxies ( M ★ > 5 × 10 10 M ⊙ ) with strong AGN-driven ionized outflows show evidence of past quenching episodes occurring within the last ∼100 − 300 Myr, mainly in the nuclear regions ( r < 3 kpc). In contrast, higher-redshift ( z > 5) and less massive ( M ★ < 10 10 M ⊙ ) starburst galaxies with powerful (starburst-driven) outflows appear to have experienced continuous growth, with no clear sign of quenching. Massive galaxies with weaker outflows do not show evidence of quenching in their history. One massive AGN host (GS20936) shows evidence of a recent (10−30 Myr) rejuvenation phase, likely fuelled by a recent major merger. This interpretation is supported by TNG300 cosmological simulations, which indicate that ∼5% of galaxies with M ★ > 5 × 10 10 M ⊙ undergo similar rejuvenation events driven by merging at z ∼ 3. These results suggest that (AGN-driven) outflows can already play a key role in shaping the SFHs of massive galaxies at early cosmic epochs, while also highlighting the importance of spatially resolved analyses for accurately reconstructing their evolutionary pathways.
Funding Information
  • Spanish Ministry of Science
  • PRIN-MUR
  • European Research Council
  • Lise Meitner Excellence Program
  • ERC APEX
  • ERDF

This publication has 146 references indexed in Scilit: