{
  "id": "1409.1690",
  "version": "v1",
  "published": "2014-09-05T08:33:54.000Z",
  "updated": "2014-09-05T08:33:54.000Z",
  "title": "X-ray emission from magnetic massive stars",
  "authors": [
    "Yael Naze",
    "Veronique Petit",
    "Melanie Rinbrand",
    "David Cohen",
    "Stan Owocki",
    "Asif ud-Doula",
    "Gregg A Wade"
  ],
  "comment": "31p, 11 figures, 8 tables - including online material, accepted for publication by ApJ",
  "categories": [
    "astro-ph.SR",
    "astro-ph.HE"
  ],
  "abstract": "Magnetically confined winds of early-type stars are expected to be sources of bright and hard X-rays. To clarify the systematics of the observed X-ray properties, we have analyzed a large series of Chandra and XMM observations, corresponding to all available exposures of known massive magnetic stars (over 100 exposures covering ~60% of stars compiled in the catalog of Petit et al. 2013). We show that the X-ray luminosity is strongly correlated with the stellar wind mass-loss-rate, with a power-law form that is slightly steeper than linear for the majority of the less luminous, lower-Mdot B stars and flattens for the more luminous, higher-Mdot O stars. As the winds are radiatively driven, these scalings can be equivalently written as relations with the bolometric luminosity. The observed X-ray luminosities, and their trend with mass-loss rates, are well reproduced by new MHD models, although a few overluminous stars (mostly rapidly rotating objects) exist. No relation is found between other X-ray properties (plasma temperature, absorption) and stellar or magnetic parameters, contrary to expectations (e.g. higher temperature for stronger mass-loss rate). This suggests that the main driver for the plasma properties is different from the main determinant of the X-ray luminosity. Finally, variations of the X-ray hardnesses and luminosities, in phase with the stellar rotation period, are detected for some objects and they suggest some temperature stratification to exist in massive stars' magnetospheres.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-09-05T08:33:54.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "magnetic massive stars",
      "x-ray emission",
      "x-ray luminosity",
      "x-ray properties",
      "stellar wind mass-loss-rate"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0067-0049/215/1/10",
      "journal": "The Astrophysical Journal Supplement Series",
      "year": 2014,
      "month": "Nov",
      "volume": 215,
      "number": 1,
      "pages": 10
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1315293,
      "adsabs": "2014ApJS..215...10N"
    }
  }
}