Detalles de publicación
PP 018035
The emission and distribution of dust of the torus of NGC 1068
(1) SOFIA/NASA, (2) IAC, (3) ULL
We present observations of NGC 1068 covering the 19.7-53.0 micron wavelength range using FORCAST and HAWC+ onboard SOFIA. Using these observations, high-angular resolution infrared (IR) and sub-mm observations, we find an observational turn-over of the torus emission in the 30-40 micron wavelength range with a characteristic temperature of 70-100 K. This component is clearly different from the diffuse extended emission in the narrow line and star formation regions at 10-100 micron within the central 700 pc. We compute 2.2-432 micron 2D images using the best inferred clumpy torus model based on several nuclear spectral energy distribution (SED) coverages. We find that when 1-20 micron SED is used, the inferred result gives a small torus size (<4 pc radius) and a steep radial dust distribution. The computed torus using the 1-432 micron SED provides comparable torus sizes, 5.1 pc radius, and morphology to the recently resolved 432 micron ALMA observations. This result indicates that the 1-20 micron wavelength range is not able to probe the full extent of the torus. The characterization of the turn-over emission of the torus using the 30-60 micron wavelength range is sensitive to the detection of cold dust in the torus. The morphology of the dust emission in our 2D image at 432 micron is spatially coincident with the cloud distribution, while the morphology of the emission in the 1-20 micron wavelength range shows an elongated morphology perpendicular to the cloud distribution. We find that our 2D clumpy torus image at 12 micron can produce comparable results to those observed using IR interferometry.

