view Abstract Citations (56) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Luminous Clusters of Wolf-Rayet Stars in the SBmIII Galaxy NGC 4214 Sargent, Wallace L. W. ; Filippenko, Alexei V. Abstract We have discovered strong, broad emission lines attributed to Wolf-Rayet (W-R) stars in spectra of several bright knots in the nearby Magellanic irregular galaxy NGC 4214. The shape of the broad blend at 4660 A shows that WC stars must be present, in addition to the generally more prevalent WN stars. This is consistent with the relatively high metallicity of NGC 4214 in comparison with most other W-R galaxies. Broad Hα emission, probably produced by late WN stars, is visible in the brightest knot; it serves as a warning that such a feature is not always an indication of Seyfert activity. If the H II regions associated with the knots are ionization bounded, the derived number ratio of W-R stars to O stars at two locations is approximately unity. Either these knots were produced by very short-lived bursts of star formation, or they have unusually flat initial mass functions. Steep spatial gradients in the intensities of the W-R lines are observed, with the strongest W-R emission lines present in knots having the brightest stellar continuum. This correlation might indicate significant spatial variations in the initial mass function, but it is more likely to be an age effect in sudden, localized starbursts. Publication: The Astronomical Journal Pub Date: July 1991 DOI: 10.1086/115859 Bibcode: 1991AJ....102..107S Keywords: Emission Spectra; Irregular Galaxies; Star Clusters; Stellar Luminosity; Wolf-Rayet Stars; Magellanic Clouds; Spectral Line Width; Stellar Spectra; Stellar Spectrophotometry; Astrophysics; GALAXIES: STRUCTURE; GALAXIES: INTERSTELLAR MATTER full text sources ADS | data products SIMBAD (12) NED (2)
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