Spider-Webb: JWST Near Infrared Camera resolved galaxy star formation and nuclear activities in the Spiderweb protocluster at z=2.16

TL;DR

This study uses JWST NIR imaging to analyze star formation and nuclear activity in high-redshift galaxies within the Spiderweb protocluster, revealing differences between star-forming galaxies and those hosting AGNs.

Contribution

First high-resolution NIR imaging of the Spiderweb protocluster with JWST, comparing star formation and AGN activity in galaxies at z=2.16.

Findings

Star formation is prominent in galactic disks of star-forming galaxies.

AGN-hosting galaxies are dominated by point sources, indicating nuclear activity.

Differences may be driven by AGN feedback effects.

Abstract

Near-infrared (NIR) emission is less affected by dust than UV and optical emission and is therefore useful for studying the properties of dust-obscured galaxies. Although rest-frame NIR observations of high-redshift galaxies have long been made using space telescopes, their structures were unresolved due to the lack of angular resolution. This letter reports the early results from the analysis of high-resolution Pa$\beta$ imaging of the Spiderweb protocluster at $z=2.16$ with the JWST Near Infrared Camera. We investigate radial profiles of Pa$\beta$ lines and rest-frame NIR continua from luminous H$\alpha$-emitting galaxies (HAEs) in the protocluster. Particularly, we compare those of 11 HAEs (N-HAEs) on the star-forming main sequence with those of 8 HAEs (X-HAEs) with X-ray AGNs. Resultant composite Pa$\beta$ line images of N-HAEs indicate significant star formation in galactic disks. In contrast, X-HAEs are dominated by point source components rather than outer star formation, as inferred from our earlier work based on multi-wavelength SED fitting. Given their higher stellar potentials suggested from their rest-frame NIR images, the different characteristics may be driven by the impact of AGN feedback.