Coded-aperture Imaging of the Galactic Center Region at Gamma-ray Energies

نویسندگان

  • WALTER R. COOK
  • JOHN M. GRUNSFELD
  • WILLIAM A. HEINDL
  • THOMAS A. PRINCE
  • STEPHEN M. ScHINDLER
  • EDwARD
  • STONE
چکیده

The first coded-aperture images of the Galactic center region at energies above 30 keV have revealed two strong y-ray sources. One source has been identified with the X-ray source 1E 1740.7-2942, located 0~8 away from the nucleus. If this source is at the distance of the Galactic center, it is one of the most luminous objects in the galaxy at energies from 35 to 200 keV. The second source is consistent in location with the X-ray source GX 354 + 0 (MXB 172834). In addition, y-ray flux from the location of GX 1 + 4 was marginally detected at a level consistent with other post-1980 measurements. No significant hard X-ray or y-ray flux was detected from the direction of the Galactic nucleus (Sgr A*), or from the direction of the recently discovered y-ray source GRS 1758-258. Subject headings: galaxies: The Galaxygamma rays: generalX-rays: sources

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تاریخ انتشار 2009