Oral Presentation
Spatially-Resolved Evidence of Inside-Out Quenching in the Spiderweb Protocluster at z~2.
Presenter: Ronaldo Laishram (National Astronomical Observatory of Japan)
We present a spatially-resolved analysis of galaxy quenching within the Spiderweb Protocluster at cosmic noon z ∼ 2.16, combining deep imaging from the James Webb Space Telescope (JWST) and the Hubble Space Telescope (HST). By employing pixel-by-pixel spectral energy distribution (SED) fitting, we derive detailed maps of stellar mass, star formation rate (SFR), specific SFR (sSFR), and rest-frame UVJ colors for star-forming and quiescent galaxy populations.
We find clear evidence for mass-dependent inside-out quenching in galaxies with log(M∗/M⊙) ≥ 10.5, characterized by systematically suppressed central star formation. These massive systems exhibit radial sSFR gradients with central values approximately one order of magnitude lower than outer regions. Lower-mass galaxies show relatively flat sSFR profiles, indicating sustained star formation across their extent. We identify a fundamental anti-correlation between Sersic index and central star formation activity, with bulge-dominated systems exhibiting reduced star formation efficiency compared to disk-dominated galaxies at fixed stellar mass surface density. Through spatially resolved UVJ color analysis, we reveal heterogeneous star formation states within individual galaxies. Star-forming spaxels in quiescent hosts occupy distinct parameter space compared to those in globally star- forming systems, while quiescent spaxels show similar properties regardless of host galaxy type. Our results demonstrate that physical mechanisms responsible for creating the present-day red sequence were already operating efficiently at z ∼ 2, with AGN feedback and morphological quenching working in concert. This study establishes cosmic noon as a critical transition period for massive galaxy evolution and provides observational constraints for galaxy formation models.
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