Nature of the emission-line region near J0320-3521

Determine whether the emission-line region approximately 1.5 kpc from quasar J0320-3521 is an interacting companion galaxy or ionized gas associated with the quasar.

Background

JWST/NIRSpec integral-field observations detect a distinct narrow-line region approximately 1.5 kpc from J0320-3521. Its small velocity offset and narrow line widths are consistent both with a companion galaxy and with low-velocity quasar-associated gas.

The available line ratios do not uniquely separate star-formation excitation in a companion from AGN-related ionization. The paper therefore identifies deeper observations of the environment and host galaxy as necessary to resolve the nature of the system.

References

From the current NIRSpec IFU data of J0320$-$3521, we cannot yet distinguish between an interacting companion galaxy and ionized gas associated with the quasar.

— Extreme Enrichment at Cosmic Dawn: Three FeII-Strong Quasars at z > 6 from the JWST Aether survey  (2609.19459 - Gloudemans et al., 16 Sep 2026) in Section 4.1, subsection “Companion galaxy or ionized gas region of J0320−3521”