{
  "id": "astro-ph/0108490",
  "version": "v1",
  "published": "2001-08-30T15:34:16.000Z",
  "updated": "2001-08-30T15:34:16.000Z",
  "title": "ASCA Observations of the Central Regions of M31",
  "authors": [
    "Hiromitsu Takahashi",
    "Yuu Okada",
    "Motohide Kokubun",
    "Kazuo Makishima"
  ],
  "comment": "12 pages, 8 figures and 5 tables; uses pasj00.cls; accepted for Publications of the Astronomical Society of Japan",
  "categories": [
    "astro-ph"
  ],
  "abstract": "Using ASCA, spatially integrated X-ray spectra of the central regions of M31 were studied. Data were accumulated over three different circular regions, with the radii of 3', 6' and 12', all centered on the nucleus. The spectra are relatively similar among the three regions. In the energy range above 1.5 keV, the spectra are reproduced by a combination of a disk black-body component and a black-body component, implying that the emission mainly comes from an assembly of low-mass X-ray binaries. In energies below 1.5 keV, the spectra involves two additional softer components, expressed with thin-thermal plasma emission models of temperatures ~ 0.9 keV and ~ 0.3 keV. Over the central 12' (2.4 kpc) region and in the 0.5-10 keV energy band, the binary component has a luminosity of 2.6 x 10^{39} erg/s, while the two softer components both exhibit luminosities of ~ 2 x 10^{38} erg/s. These results are compared with those from other missions, including Chandra and XMM-Newton in particular. Discussion is made on the nature of the two softer spectral components besides the binary one.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2001-08-30T15:34:16.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "central regions",
      "asca observations",
      "thin-thermal plasma emission models",
      "kev energy band",
      "low-mass x-ray binaries"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1093/pasj/53.5.875"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 576559
    }
  }
}