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High-Resolution Mid-Infrared Imaging of G339.88-1.26

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 نشر من قبل James M. De Buizer
 تاريخ النشر 2001
  مجال البحث فيزياء
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G339.88-1.26 is considered to be a good candidate for a massive star with a circumstellar disk. This has been supported by the observations of linearly distributed methanol maser spots believed to delineate this disk, and mid-infrared observations that have discovered a source at this location that is elongated at the same position angle as the methanol maser distribution. We used the mid-infrared imager/spectrometer OSCIR at Keck to make high-resolution images of G339.88-1.26. We resolve the mid-infrared emission into 3 sources within 1.5 arcsec of the location of the masers. We determine that the methanol masers are most likely not located in a circumstellar disk. Furthermore we find that the observed radio continuum emission most likely comes from two sources in close proximity to each other. One source is an unobscured massive star with an extended HII region that is responsible for the peak in the radio continuum emission. A second source is embedded and centered on the elongation in the radio continuum emission that is believed to be tracing an outflow in this region.



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