Do Ultraluminous X-Ray Sources Really Contain Intermediate-Mass Black Holes?

  title={Do Ultraluminous X-Ray Sources Really Contain Intermediate-Mass Black Holes?},
  author={Kiki VierdayantiShin Mineshige and Ken Ebisawa Institute of Space and Astronautical Science and Japan Aerospace Exploration Agency and Toshihiro Kawaguchi},
  journal={Publications of the Astronomical Society of Japan},
An open question remains whether Ultraluminous X-ray Sources (ULXs) really contain intermediate-mass black holes (IMBHs). We carefully investigated the XMM-Newton EPIC spectra of four ULXs that were claimed to be strong candidates of IMBHs by several authors. Wefirst triedfitting by the standard spectral model of disk blackbody (DBB) + power-law (PL), finding good fits to all of the data, in agreement with others. We, however, found that the PL component dominates the DBB component at ∼ 0.3 to… Expand

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