Silencing the Giant: Evidence of Active Galactic Nucleus Feedback and Quenching in a Little Red Dot at z = 4.13

Abstract

The James Webb Space Telescope (JWST) has uncovered a ubiquitous population of dust-obscured compact sources at z ≳ 4. Many of these objects exhibit signs of active galactic nucleus (AGN) activity, making their study crucial for understanding the formation of supermassive black holes (SMBHs) and their growth with host galaxies. In this work, we examine low and medium-resolution JWST/NIRSpec spectra from the JADES GTO public data release in the GOODS-N field of a red, luminous ( M B ∼ −22.2 mag) and compact (<500 pc) source at z = 4.13. The rest-optical ( λ rest > 4000 Å) continuum of this source is strongly dominated by a massive (log 10 [ M * / M ⊙ ] ∼ 10.6), quenched (log 10 [sSFR/yr −1 ]