Digest
Paper II expands the JWST/NIRCam morphology work by adding four metrics to shape asymmetry and introducing matched inactive controls for 425 Seyfert-luminosity AGN at 0.6<z<2.4 in GOODS-N/S. The analysis classifies major versus minor mergers and finds a high merger fraction among obscured, sub‑quasar hosts, with major mergers dominant and rising toward higher redshift. Disturbance patterns differ for X-ray- versus mid-IR-selected AGN, consistent with sequential phases in a major‑merger timeline (mid‑IR/X‑ray‑faint preceding X‑ray‑bright). These results argue that mergers are an important trigger of Seyfert activity at Cosmic Noon.
Key figures to inspect
- Figure 1 — Verify that the control samples (CANDELS near-IR, MIRI-selected, and X-ray-selected) are well matched in stellar mass and redshift to the AGN, ensuring morphology contrasts are not driven by selection effects.
- Figure 2 — Inspect F150W cutouts illustrating major, minor, and non‑merger labels; look for tidal tails, wisps, edges, and multiple nuclei that underpin the combined indicator-based staging of the merger sequence.
- Figure 3 — Read off the major, minor, and total merger fractions versus redshift (and N_H color-coding, including simulated CT mid‑IR AGN); note the dominance of major mergers and the rise of total merger incidence with redshift.
- Figure 4 — From Paper I, examine how shape asymmetry increases with obscuration and redshift; the clustering at high A_S and high N_H highlights the early, chaotic stage of mergers relevant to this sample.