SOFIA/FORCAST OBSERVATIONS OF WARM DUST IN S106: A FRAGMENTED ENVIRONMENT

We present mid-IR (19-37 pm) imaging observations of S106 from SOFIA/FORCAST, complemented with IR observations from SpitzerlIRAC (3.6-8.0 mu m), IRTF/MIRLIN (11.3 and 12.5 mu m), and HerschelIPACS (70 and 160 pm). We use these observations, observations in the literature, and radiation transfer modeling to study the heating and composition of the warm (similar to 100 K) dust in the region. The dust is heated radiatively by the source S106 IR, with little contributions from grain-electron collisions and Ly alpha radiation. The dust luminosity is greater than or similar to(9.02 +/- 1.01) x 10(4) L-circle dot), consistent with heating by a mid- to late-type 0 star. We find a temperature gradient (similar to 75-107 K) in the lobes, which is consistent with a dusty equatorial geometry around S106 IR. Furthermore, the SOFIA observations resolve several cool (similar to 65-70 K) lanes and pockets of warmer (similar to 75-90 K) dust in the ionization shadow, indicating that the environment is fragmented. We model the dust mass as a composition of amorphous silicates, amorphous carbon, big grains, very small grains, and polycyclic aromatic hydrocarbons. We present the relative abundances of each grain component for several locations in S106.