Spider-Webb: Spatially-Resolved Evidence of Inside-Out Quenching in the Spiderweb Protocluster at $z \sim 2$

Ronaldo Laishram; Yusei Koyama; Abdurrahman Naufal; Tadayuki Kodama; Rhythm Shimakawa; Kazuki Daikuhara; Helmut Dannerbauer; Jose Manuel Pérez-Martínez; Pablo G. Pérez-González

arXiv · 2512.18805

Spider-Webb: Spatially-Resolved Evidence of Inside-Out Quenching in the Spiderweb Protocluster at $z \sim 2$

Ronaldo Laishram·Yusei Koyama·Abdurrahman Naufal·Tadayuki Kodama·Rhythm Shimakawa·Kazuki Daikuhara·Helmut Dannerbauer·Jose Manuel Pérez-Martínez·Pablo G. Pérez-González

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Abstract

We present a spatially-resolved analysis of galaxy quenching within the Spiderweb Protocluster at $z \sim 2.16$, combining deep imaging from the James Webb Space Telescope (JWST) and the Hubble Space Telescope (HST). Utilizing pixel-by-pixel spectral energy distribution fitting, we derive maps of stellar mass, star formation rate (SFR), specific SFR (sSFR), and rest-frame UVJ colors. Quiescent galaxies, predominantly found at $\log(M_*/M_{\odot}) \geq 10.5$, exhibit clear mass-dependent inside-out quenching, with central sSFR approximately an order of magnitude lower than outer regions, while lower-mass star-forming galaxies show flat sSFR profiles. Central star formation activity fundamentally anti-correlates with S\'ersic index, indicating reduced activity in bulge-dominated systems. Spatially resolved UVJ colors reveal heterogeneous internal star formation, distinguishing star-forming regions in quiescent hosts from those in globally star-forming systems. These findings demonstrate that quenching mechanisms were effectively operating by $z \sim 2$, with the observed inside-out patterns and morphological correlations consistent with AGN-driven feedback processes. Our study provides key observational constraints on galaxy evolution during this critical epoch.

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Ronaldo Laishram, Yusei Koyama, Abdurrahman Naufal, Tadayuki Kodama, Rhythm Shimakawa, Kazuki Daikuhara, Helmut Dannerbauer, Jose Manuel Pérez-Martínez, Pablo G. Pérez-González. 2025-12-21. Spider-Webb: Spatially-Resolved Evidence of Inside-Out Quenching in the Spiderweb Protocluster at $z \sim 2$. https://arxiv.org/abs/2512.18805

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