Origin of unrecovered AGB candidates from the Kerschbaum et al. catalogue

Determine why candidate asymptotic giant branch stars reported by Kerschbaum et al. in Andromeda II are not recovered in the UKIRT/WFCAM catalogue, distinguishing the effects of positional offsets, source classification, foreground contamination, photometric limits, and chance cross-matches.

Background

The study cross-matches its UKIRT/WFCAM detections with previously published AGB-star catalogues. Although increasing the cross-match radius recovers additional Kerschbaum et al. sources, many unmatched objects are classified as non-stellar, noise-like, or foreground sources in the new data.

The paper notes that the earlier catalogue may have systematic positional offsets and that some sources may be chance alignments, but it does not establish a definitive explanation for the unmatched population.

References

However, this is not seen in the \citet{Kerschbaum2004} sample, where unmatched sources span a similar magnitude range to those recovered. The reason for the unrecovered sources in the \citet{Kerschbaum2004} sample is unclear.

— A near-IR survey of luminous asymptotic giant branch stars in the satellites and stellar halo of M31  (2609.20810 - Howell et al., 17 Sep 2026) in Section 5.1, Comparison with previous work