Determine the origin of C IV emission in Little Red Dots

Determine whether C IV emission detected in Little Red Dots originates from the compact Little Red Dot component or from its host galaxy, and identify the ionizing source, intrinsic emission region, and intervening gas responsible for the observed line emission.

Background

The paper discusses C IV detections in Little Red Dots, where strong C IV and weak or undetected He II have often been interpreted through stellar photoionization. However, the observations do not uniquely locate the C IV-emitting region or establish the relevant ionizing source and propagation medium. The authors propose spatially and spectrally resolved joint observations of C IV, He II, and Balmer lines as a way to resolve these uncertainties.

References

However, current observations do not uniquely determine whether C~IV is produced by the compact LRD component or its host galaxy. Moreover, the ionizing source, the intrinsic emission region, and the gas through which the photons propagate are physically different.

— Tracing Warm Gas through C IV Radiative Transfer  (2609.11487 - Lim et al., 10 Sep 2026) in Section 5.3, Implications for C IV emission in Little Red Dots