SOFIA/FORCAST Observations of Warm Dust in S106: A Fragmented Environment

November 2015 • 2015ApJ...814...54A

Authors • Adams, J. D. • Herter, T. L. • Hora, J. L. • Schneider, N. • Lau, R. M. • Staguhn, J. G. • Simon, R. • Smith, N. • Gehrz, R. D. • Allen, L. E. • Bontemps, S. • Carey, S. J. • Fazio, G. G. • Gutermuth, R. A. • Guzman Fernandez, A. • Hankins, M. • Hill, T. • Keto, E. • Koenig, X. P. • Kraemer, K. E. • Megeath, S. T. • Mizuno, D. R. • Motte, F. • Myers, P. C. • Smith, H. A.

Abstract • We present mid-IR (19-37 μm) imaging observations of S106 from SOFIA/FORCAST, complemented with IR observations from Spitzer/IRAC (3.6-8.0 μm), IRTF/MIRLIN (11.3 and 12.5 μm), and Herschel/PACS (70 and 160 μm). We use these observations, observations in the literature, and radiation transfer modeling to study the heating and composition of the warm (∼100 K) dust in the region. The dust is heated radiatively by the source S106 IR, with little contributions from grain-electron collisions and Lyα radiation. The dust luminosity is ≳(9.02 ± 1.01) × 104 L, consistent with heating by a mid- to late-type O star. We find a temperature gradient (∼75-107 K) in the lobes, which is consistent with a dusty equatorial geometry around S106 IR. Furthermore, the SOFIA observations resolve several cool (∼65-70 K) lanes and pockets of warmer (∼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.


IPAC Authors

Sean Carey

Senior Scientist