Nature of the faint emission-line structure near J0216-5226

Identify the source responsible for the faint emission-line structure approximately 1 arcsecond northwest of quasar J0216-5226 and determine whether it is a genuine companion or ionized-gas feature.

Background

A tentative structure is detected northwest of J0216-5226 in several integrated emission-line maps, but it disappears under a stricter signal-to-noise threshold and its extracted spectrum is dominated by noise.

Although its repeated appearance in multiple maps suggests that it may not be an artifact, the available data do not establish its identity. The paper calls for deeper integral-field observations to confirm and characterize the feature.

References

To confirm and investigate the nature of this emission region, deeper IFU observations are necessary.

— 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 4.3, subsection “Faint emission-line region of J0216−5226”