{
  "id": "1112.4290",
  "version": "v2",
  "published": "2011-12-19T10:31:11.000Z",
  "updated": "2012-02-29T08:24:53.000Z",
  "title": "X-ray activity and rotation of the young stars in IC 348",
  "authors": [
    "Frauke Alexander",
    "Thomas Preibisch"
  ],
  "comment": "accepted by A&A on 15th of December 2011 published in Astronomy & Astrophysics Februar 2012",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "The physical origin of the strong magnetic activity in T Tauri stars and its relation to stellar rotation is not yet well understood. We investigate the relation between the X-ray activity, rotation, and Rossby number for a sample of 82 young stars in the ~3 Myr old cluster IC 348. We use the data of four Chandra observations of IC 348 to derive the X-ray luminosities of the young stars. The young stars in IC 348 show no correlation between X-ray activity and rotation period. Considering the Rossby numbers, nearly all IC 348 stars are in the saturated regime of the activity-rotation relation defined by main-sequence stars. Searching for possible super-saturation effects, we find a marginal (but statistically in-significant) trend that the stars with the smallest Rossby numbers show slightly lower X-ray activity levels. We compare the dispersion of fractional X-ray luminosities of the stars in the saturated rotation regime in IC 348 to that seen in younger and older stellar populations. The scatter seen in the ~3 Myr old IC 348 is considerably smaller than for the ~1 Myr old ONC, but, at the same time, considerably larger than the dispersion seen in the ~30 Myr old cluster NGC 2547 and in main-sequence stars. The results of our X-ray analysis of IC 348 show that neither the rotation rates nor the presence/absence of circumstellar disks are of fundamental importance for determining the level of X-ray activity in TTS. Our results suggest that the scatter of X-ray activity levels shown by the fast-rotating members of young clusters decreases with the age of the stellar population. We interpret this as a signature of the changing interior structure of PMS stars and the consequent changes in the dynamo mechanisms that are responsible for the magnetic field generation.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2012-02-29T08:24:53.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "young stars",
      "rossby number",
      "myr old cluster ic",
      "stellar population",
      "x-ray luminosities"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1051/0004-6361/201118100",
      "journal": "Astronomy and Astrophysics",
      "year": 2012,
      "month": "Mar",
      "volume": 539
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1082068,
      "adsabs": "2012A&A...539A..64A"
    }
  }
}