The Stellar Content of Obscured Galactic Giant H II Regions : II . W 42
نویسنده
چکیده
We present near infrared J, H, and K images and K−band spectroscopy in the giant H II region W42. A massive star cluster is revealed; the color–color plot and K−band spectroscopic morphology of two of the brighter objects suggest the presence of young stellar objects. The spectrum of the bright central star is similar to unobscured stars with MK spectral types of O5–O6.5. If this star is on the zero age main sequence, then the derived spectrophotometric distance is considerably smaller than previous estimates. The Lyman continuum luminosity of the cluster is a few times that of the Trapezium. The slope of the K−band luminosity function is similar to that for the Trapezium cluster and significantly steeper than that for the massive star cluster in M17 or the Arches cluster near the Galactic center.
منابع مشابه
The Stellar Content of Obscured Galactic Giant1 H II Regions: I. W43
Near infrared images of the Galactic giant H II region W43 reveal a dense stellar cluster at its center. Broad band JHK photometry of the young cluster and K−band spectra of three of its bright stars are presented. The 2 μm spectrum of the brightest star in the cluster is very well matched to the spectra of Wolf–Rayet stars of sub–type WN7. Two other stars are identified as O type giants or sup...
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