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arXiv · astro-ph/9704101

Properties of H II Regions in the Centers of Nearby Galaxies

Luis C. Ho·Alexei V. Filippenko·Wallace L. W. Sargent
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Abstract

As part of an optical spectroscopic survey of nearby, bright galaxies, we have identified a sample of over 200 emission-line nuclei having optical spectra resembling those of giant extragalactic H II regions. Such "H II nuclei," powered by young, massive stars, are found in a substantial fraction of nearby galaxies, especially those of late Hubble type. This paper summarizes the observational characteristics of H II nuclei, contrasts the variation of their properties with Hubble type, and compares the nuclear H II regions with those found in galaxy disks. Similarities and differences between H II nuclei and luminous starburst nuclei are additionally noted.

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Luis C. Ho, Alexei V. Filippenko, Wallace L. W. Sargent. 1997-04-11. Properties of H II Regions in the Centers of Nearby Galaxies. https://doi.org/10.1086/304642

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