Low-Level Nuclear Activity in Nearby Spiral Galaxies

@article{Ghosh2008LowLevelNA,
  title={Low-Level Nuclear Activity in Nearby Spiral Galaxies},
  author={Himel Ghosh and Smita Mathur and Fabrizio Fiore and Laura Ferrarese},
  journal={The Astrophysical Journal},
  year={2008},
  volume={687},
  pages={216 - 229}
}
We are conducting a search for supermassive black holes (SMBHs) with masses below ~107 M☉ by looking for signs of extremely low-level nuclear activity in nearby galaxies that are not known to be AGNs. Our survey has the following characteristics: (1) X-ray selection using the Chandra X-Ray Observatory, since X-rays are a ubiquitous feature of AGNs; (2) emphasis on late-type spiral and dwarf galaxies as the galaxies most likely to have low-mass SMBHs; (3) use of multiwavelength data to verify… 

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