Imaging and Spatially Resolved Spectroscopy of AFGL 2688 in the Thermal Infrared Region

摘要: We present ground-based high-resolution (~0".3) imaging of AFGL 2688 at L' (3.8 um) and M'(4.7um). A wealth structure in the central region is revealed due to less extinction thermal infrared. clear border southern lobe corresponds edge heavily obscured visible, indicating there a dense material surrounding region. The images also show narrow dark lane oriented 140 deg east north with normal 50 deg. position angle inconsistent optical polar axis (PA = 15 deg), but aligned high-velocity CO components found radio wavelength observations. star remains invisible M'. Several clumpy regions dominate M' luminosity. In particular pointlike source (peak A) 0".5 northeast center nebula exhibits highest surface brightness very red spectral energy distribution (SED). Based on almost identical SED as adjacent regions, we suggest that not self-luminous, was proposed, dusty blob reflecting emission from star. We spatially resolved slit spectroscopy bright blobs. An feature 3.4 um well 3.3 detected everywhere within our field view. There no spatial variation infrared (IEF) throughout observed area (0".2-1".5, or 240-1800 AU source). constant flux ratio relative continuum consistent view blobs are mostly light 3