The Nature of Ultraluminous Compact X-Ray Sources in Nearby Spiral Galaxies

  title={The Nature of Ultraluminous Compact X-Ray Sources in Nearby Spiral Galaxies},
  author={Kazuo Makishima and Aya Kubota and Tsunefumi Mizuno and Tomohisa Ohnishi and Makoto Tashiro and Yoichi Aruga and Kazumi Asai and Tadayasu Dotani and Kazuhisa Mitsuda and Yoshihiro Ueda and Shinichiro Uno and Kazutaka Yamaoka and Ken Ebisawa and Yoshiki Kohmura and Kyoko Okada University of Tokyo and Institute of Space and Astronautical Science and Nasa Goddard Space Flight Center and Harima Institute},
  journal={The Astrophysical Journal},
Studies were made of ASCA spectra of seven ultraluminous compact X-ray sources in nearby spiral galaxies: M33 X-8, M81 X-6, IC 342 source 1, Dwingeloo 1 X-1, NGC 1313 source B, and two sources in NGC 4565. With the 0.5-10 keV luminosities in the range 1039-1040 ergs s-1, they are thought to represent a class of enigmatic X-ray sources often found in spiral galaxies. For some of them, the ASCA data are newly processed or the published spectra are reanalyzed. For others, the published results are… Expand

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