Mid infrared emission of nearby Herbig Ae / Be stars ?
نویسنده
چکیده
We present mid IR spectro-photometric imaging of a sample of eight nearby (D ≤ 240 pc) Herbig Ae/Be stars. The spectra are dominated by photospheric emission (HR6000), featureless infrared excess emission (T Cha), broad silicate emission feature (HR5999) and the infrared emission bands (HD 97048, HD 97300, TY CrA, HD 176386). The spectrum of HD179218 shows both silicate emission and infrared emission bands (IEB). All stars of our sample where the spectrum is entirely dominated by IEB have an extended emission on scales of a few thousand AU (∼ 10′′). We verify the derived source extension found with ISOCAM by multi–aperture photometry with ISOPHT and compare our ISOCAM spectral photometry with ISOSWS spectra.
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