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

L. Ulivi, M. Perna, S. Arribas, B. Rodríguez Del Pino, P. G. Pérez-González, I. Lamperti, C. Marconcini, H. Übler, F. D'Eugenio, T. Böker, A. J. Bunker, S. Carniani, S. Charlot, R. Maiolino, P. Alvarez, E. Bertola, G. Cresci, M. Curti, M. Hamed, L. R. Ivey, G. C. Jones, E. Parlanti, R. Pascalau, C. Prieto Jimenez, B. Trefoloni, G. Venturi, S. Zamora

First listed 2026-06-15 | Last updated 2026-06-11

Abstract

The study of starburst- and 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 JWST/NIRSpec IFU in low- ($R \sim 100$) and high-resolution ($R \sim 2700$) mode. Previous analysis of $R \sim 2700$ data revealed ionized outflows in all these galaxies. We explore possible links between outflows and stellar population properties to assess the mechanisms driving galaxy evolution at early epochs. Combining the spatially resolved stellar population analysis with the outflow properties, we find that the most massive galaxies ($M_\star > 5 \times 10^{10} M_\odot$) with strong AGN-driven ionized outflows show evidence of past quenching episodes occurring within the last $\sim 100$--$300$ Myr, mainly in the nuclear regions ($r < 3$ kpc). In contrast, higher-redshift ($z > 5$) and less massive ($M_\star < 10^{10} M_\odot$) 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 for a recent ($10$--$30$ Myr) rejuvenation phase, likely fueled by a recent major merger. These results suggest that (AGN-driven) outflows can already play a key role in shaping the SFHs of massive galaxies at early cosmic epochs.

Short digest

This GA-NIFS paper uses JWST/NIRSpec IFU prism and R≈2700 data for six galaxies at 3<z<9 to connect previously identified ionized outflows with spatially resolved stellar populations and star-formation histories. It finds that the massive systems with strong AGN-driven outflows (M⋆>5×10^10 M⊙) show nuclear quenching episodes within the last ≈100–300 Myr, while the lower-mass z>5 starbursts with powerful starburst-driven outflows are consistent with continuous growth and no clear quenching. A second major result is methodological: unresolved stellar masses are systematically biased low, by as much as ≈0.75 dex at high sSFR, because spatially mixed young populations outshine older stellar mass. GS20936 is the standout rejuvenation case, with a likely merger-fueled 10–30 Myr restart of star formation that sharpens the paper’s case that resolved JWST data can separate quenching, continued growth, and renewed activity in early massive galaxies. ([arxiv.org](https://arxiv.org/abs/2606.13819))

Key figures to inspect

• Figure 1. Use the opening sample-and-data overview to establish the six-object GA-NIFS set across 3<z<9, the split between AGN- and starburst-dominated systems, and the combined NIRSpec IFU low-resolution prism plus high-resolution R≈2700 setup that underpins the resolved stellar-population and outflow comparison in the rest of the paper. ([arxiv.org](https://arxiv.org/abs/2606.13819))
• Figure 4. Prioritize the figure that compares unresolved and spatially resolved Prospector-derived stellar masses or SFHs, because the paper treats the outshining bias as a major practical result: integrated measurements miss stellar mass increasingly badly toward high sSFR, reaching discrepancies of about 0.75 dex. ([arxiv.org](https://arxiv.org/abs/2606.13819?utm_source=openai))
• Figure 7. Choose the later resolved diagnostic figure that overlays or directly compares stellar-population age or SFH structure with the ionized-outflow geometry in the massive AGN hosts, since this is the main evidence for recent 100–300 Myr quenching concentrated in the inner r<3 kpc rather than a galaxy-wide shutdown. ([arxiv.org](https://arxiv.org/abs/2606.13819?utm_source=openai))
• Figure 9. Include the paper’s late synthesis or comparison figure that separates strong AGN-driven outflow systems, weaker-outflow massive galaxies, and low-mass high-z starbursts by SFH behavior, because that is where the central claim becomes clearest: only the strong AGN-outflow massive galaxies show convincing quenching signatures, while the starbursts continue growing. ([arxiv.org](https://arxiv.org/abs/2606.13819?utm_source=openai))