{
  "id": "2108.05172",
  "version": "v1",
  "published": "2021-08-11T12:00:21.000Z",
  "updated": "2021-08-11T12:00:21.000Z",
  "title": "Clean catalogues of blue horizontal-branch stars using Gaia EDR3",
  "authors": [
    "Richard Culpan",
    "Ingrid Pelisoli",
    "Stephan Geier"
  ],
  "comment": "14 pages, 16 figures. To be published in Astronomy & Astrophysics 14. Catalogs and data section. The catalogues are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/",
  "categories": [
    "astro-ph.SR",
    "astro-ph.GA"
  ],
  "abstract": "Context: Blue horizontal-branch stars are very old objects that can be used as markers in studies of the Galactic structure and formation history. To create a clean sky catalogue of blue horizontal-branch stars, we cross-matched the Gaia data release 2 (DR2) dataset with existing reference catalogues to define selection criteria based on Gaia DR2 parameters. Following the publication of Gaia early data release 3 (EDR3), these methods were verified and subsequently applied to this latest release. Aims: The purpose of this catalogue is to identify a set of blue horizontal-branch star candidates that have been selected using photometric and astrometric observations and exhibits a low contamination rate. Methods: We cross-matched reference blue horizontal-branch datasets with the Gaia DR2 database and defined two sets of selection criteria. Firstly, in Gaia DR2 - colour and absolute G magnitude space, and secondly, in Gaia DR2 - colour and reduced proper motion space. The main-sequence contamination in both subsets of the catalogue was reduced, at the expense of completeness, by concentrating on the Milky Way's Galactic halo, where relatively young main-sequence stars were not expected. Results: We present a catalogue, based on Gaia EDR3, of 57,377 blue horizontal-branch stars. The Gaia EDR3 parallax was used in selecting 16,794 candidates and the proper motions were used to identify a further 40,583 candidates.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-08-11T12:00:21.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "gaia edr3",
      "gaia dr2",
      "clean catalogues",
      "cross-matched reference blue horizontal-branch datasets",
      "blue horizontal-branch star candidates"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}