On the Anisotropy of Nuclei Mid-Infrared Radiation in Nearby Active Galactic Nuclei

摘要: In the center of active galactic nuclei (AGN), dusty torus absorb radiation from central engine and re-emit in mid-infrared (MIR). Observations have detected moderate anisotropy dust MIR emission, way that type 1 AGNs (type1s) are mildly brighter comparing with 2 sources (type2s). However, type1s type2s were found to follow statistically same tight -- hard X-ray correlation, suggesting emission is highly isotropic assuming inclination independent. We argue this discrepancy could be solved considering AGN also anisotropic as we recently discovered. To verify diagram, compare sub-arcsecond 12\mu m flux densities using [OIV]$\lambda$25.89\mu line an luminosity indicator. find on average by a factor $2.6 \pm 0.6$ than at given luminosities, confirming mild emission. show good agreement radiative transfer models clumpy torus. The fact correlation instead supports both anisotropic.