ROSAT X-Ray Observations of the Spiral Galaxy M81

  title={ROSAT X-Ray Observations of the Spiral Galaxy M81},
  author={Stefan Immler and Q. Daniel Wang},
  journal={The Astrophysical Journal},
We present results from the analysis of deep ROSAT HRI and PSPC observations of the spiral galaxy M81. The inferred total (0.5-2 keV band) luminosity of M81 is ~3 × 1040 ergs s-1, excluding the contribution from identified interlopers found within the D25 ellipse. The nucleus of the galaxy alone accounts for about 65% of this luminosity. The rest is due to 26 other X-ray sources (contributing ~10%) and to apparently diffuse emission, which is seen across much of the galactic disk and is… 

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