{
  "id": "1302.0068",
  "version": "v1",
  "published": "2013-02-01T03:51:11.000Z",
  "updated": "2013-02-01T03:51:11.000Z",
  "title": "XMM-Newton Observations of the TeV γ-ray Source HESS J1804-216",
  "authors": [
    "Dacheng Lin",
    "Natalie A. Webb",
    "Didier Barret"
  ],
  "comment": "Accepted for Publication in ApJ. 20 pages (single column), 6 figures",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We have analyzed three XMM-Newton observations of the central part of the unidentified TeV \\gamma-ray source HESS J1804-216. We focus on two X-ray sources 2XMMi J180442.0-214221 (Src 1) and 2XMMi J180432.5-214009 (Src 2), which were suggested to be the possible X-ray counterparts to the TeV source. We discover a 2.93 hr X-ray periodicity from Src 1, with the pulse profile explained with a self-eclipsing pole in an eclipsing polar. Src 2 exhibits a strong Fe emission line (FWHM ~0.3 keV and equivalent width ~0.8 keV) and large X-ray variability on timescales of hours and is probably an intermediate polar. Thus Src 1 and Src 2 are probably two field sources not responsible for the TeV emission. The observations were contaminated by strong straylight from a nearby bright source, and we see no clear extended X-ray emission that can be attributed to the supernova remnant G8.7-0.1, a popular possible association with the TeV source. The other possible association, the pulsar wind nebula candidate PSR J1803-2137, shows little long-term variability, compared with a previous Chandra observation. Many point sources were serendipitously detected, but most of them are probably normal stars. Three new candidate compact object systems (other than Src 1, Src 2 and PSR J1803-2137) are also found. They are far away from the TeV source and are probably also magnetic cataclysmic variables, thus unlikely to be responsible for the TeV emission.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2013-02-01T03:51:11.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "xmm-newton observations",
      "source hess",
      "tev source",
      "pulsar wind nebula candidate psr",
      "tev emission"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/766/1/29",
      "journal": "The Astrophysical Journal",
      "year": 2013,
      "month": "Mar",
      "volume": 766,
      "number": 1,
      "pages": 29
    },
    "note": {
      "typesetting": "TeX",
      "pages": 20,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1217363,
      "adsabs": "2013ApJ...766...29L"
    }
  }
}