A near-IR survey of luminous asymptotic giant branch stars in the satellites and stellar halo of M31

Clicks: 9
ID: 329326
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #1,283 of 1,339 articles by views in monthly notices of the royal astronomical society

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 1,339 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Abstract We investigate the dwarf spheroidal (dSph) satellites and stellar halo of M31 using near-infrared imaging from the Wide-Field Camera on the UKIRT 3.8 m telescope. Our homogeneous analysis covers the stellar extents of 12 dSphs, as well as their surrounding halo field populations. We identify carbon-rich (C) and oxygen-rich (M) thermally-pulsing AGB stars (TP-AGBs) using colour-magnitude and colour-colour diagrams, which also allows for effective contaminant rejection. TP-AGB stars are detected in eight of the 12 dSphs, indicating small intermediate-age populations in a substantial fraction of the sample; they are also found in considerable numbers throughout most of M31’s stellar halo. By combining 316 new detections with a revised classification of objects previously reported in the literature, we increase the TP-AGB candidate population in the dSphs from 82 to 359. We use the resulting dSph and halo AGB samples to compute C/M ratios and infer metallicities in the dSphs and adjacent halo fields with non-zero AGB counts. A clear metallicity gradient is observed in the M31 stellar halo out to ~150 kpc, consistent with that found using other tracers. Using literature star formation histories from main-sequence turn-off photometry, we find a tight correlation between the number of C stars in the dSphs and the stellar mass formed in the last 0.5–3 Gyr. This study underscores the promise of AGB stars as quantitative tracers of intermediate-age star formation, particularly in intrinsically faint systems, and provides a catalogue of candidate TP-AGB stars for follow-up.
Reference Key
openalex_W7213590878 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Jess M. Howell, Annette M. N. Ferguson, Olivia C. Jones, Mike. J. Irwin, Maria-Rosa L. Cioni, Geraint F. Lewis, Nicolas. F. Martin, Alan. W. McConnachie
Are you one of these authors? Claim your profile
Journal monthly notices of the royal astronomical society
Year 2026
DOI
10.1093/mnras/stag1779
URL
https://doi.org/10.1093/mnras/stag1779
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.