XMM-Newton observation of the galactic centre - evidence against the X-ray reflection nebulae model?

被引:29
作者
Predehl, P [1 ]
Costantini, E [1 ]
Hasinger, G [1 ]
Tanaka, Y [1 ]
机构
[1] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany
关键词
Galaxy : center; X-rays;
D O I
10.1002/asna.200310019
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present preliminary results of a 50 ksec XMM-Newton observation of the Galactic Centre. Due to the excellent spectral resolution of XMM-Newton combined with its high throughput at energies even beyond 7 keV, the iron line complex could be resolved into individual components (neutral. ionized, both in Kalpha and Kbeta) in the spectra of a number of sources. In the spectrum of Sgr A East, we find an overabundance of iron, although less than reported in a recent analysis of Chandra data. No flare from Sgr A* was detected. The large scale diffuse emission seen already by Einstein, ROSAT, and ASCA extending into the north-cast direction is most probably of thermal origin. This region extends from Sgra A East also towards both directions perpendicular to the Galactic Plane ("outflow") and contains some blobs of plasma with a higher temperature. Particularly interesting is the map of the 6.4 keV fluorescence line of neutral iron which shows a very peculiar filamentary structure. Spectral modelling of these filaments is obviously not in agreement with the X-ray reflection nebulae (XRN) model commonly discussed for the origin of the fluorescence line, primarily because we do not see a significant iron absorption edge at 7.1 keV.
引用
收藏
页码:73 / 76
页数:4
相关论文
共 15 条
  • [1] Rapid X-ray flaring from the direction of the supermassive black hole at the Galactic Centre
    Baganoff, FK
    Bautz, MW
    Brandt, WN
    Chartas, G
    Feigelson, ED
    Garmire, GP
    Maeda, Y
    Morris, M
    Ricker, GR
    Townsley, LK
    Walter, F
    [J]. NATURE, 2001, 413 (6851) : 45 - 48
  • [2] BAGANOFF FK, 2001, UNPUB APJ
  • [3] GOLDWURM A, 2002, UNPUB APJ
  • [4] ASCA view of our galactic center: Remains of past activities in X-rays?
    Koyama, K
    Maeda, Y
    Sonobe, T
    Takeshima, T
    Tanaka, Y
    Yamauchi, S
    [J]. PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 1996, 48 (02) : 249 - 255
  • [5] KOYAMA K, 2002, ESA
  • [6] A Chandra study of Sagittarius A East:: A supernova remnant regulating the activity of our Galactic center?
    Maeda, Y
    Baganoff, FK
    Feigelson, ED
    Morris, M
    Bautz, MW
    Brandt, WN
    Burrows, DN
    Doty, JP
    Garmire, GP
    Pravido, SH
    Ricker, GR
    Townsley, LK
    [J]. ASTROPHYSICAL JOURNAL, 2002, 570 (02) : 671 - 687
  • [7] ASCA observations of the sagittarius B2 cloud:: An X-ray reflection-nebula
    Murakami, H
    Koyama, K
    Sakano, M
    Tsujimoto, M
    Maeda, Y
    [J]. ASTROPHYSICAL JOURNAL, 2000, 534 (01) : 283 - 290
  • [8] ASCA discovery of diffuse 6.4 keV emission near the Sagittarius C complex:: A new X-ray reflection nebula
    Murakami, H
    Koyama, K
    Tsujimoto, M
    Maeda, Y
    Sakano, M
    [J]. ASTROPHYSICAL JOURNAL, 2001, 550 (01) : 297 - 300
  • [9] PREDEHL P, 1995, ASTRON ASTROPHYS, V293, P889
  • [10] SAKANO M, UNPUB MNRAS