The location of warm dust producing the Mid-infrared ( MIR ) emission in Type 1 Active Galactic Nuclei ( AGNs ) is complex and not yet fully known .
We explore this problem by studying how the MIR covering factor ( CF _ { MIR } = L _ { MIR } / L \mathrm { { } _ { bol } } ) correlates with the fundamental parameters of AGN accretion process ( such as L \mathrm { { } _ { bol } } , black hole mass M _ { \mathrm { BH } } , and Eddington ratio L / L \mathrm { { } _ { Edd } } ) and the properties of narrow emission lines ( as represented by [ O III ] \lambda 5007 ) , using large data sets derived from the Sloan Digital Sky Spectroscopic Survey ( SDSS ) and the Wide Infrared Sky Survey ( WISE ) .
Firstly we find that the luminosity of the [ O III ] wing component ( L _ { wing } ) correlates more tightly with the continuum luminosity ( \lambda L _ { \lambda } ( 5100 ) ) than the luminosity of the line core component ( L _ { core } ) does , which is in line with our previous conclusion that the wing component , generally blueshifted , originates from the polar outflows in the inner narrow-line region ( NLR ) .
We then find that the MIR CF shows the strongest correlation with L _ { wing } / L \mathrm { { } _ { bol } } rather than with L _ { core } / L \mathrm { { } _ { bol } } or the above fundamental AGN parameters , and the correlation becomes stronger as the infrared wavelength increases .
We also confirm the anti-correlations of CF _ { MIR } with L \mathrm { { } _ { bol } } and M _ { \mathrm { BH } } , and the lack of dependence of CF _ { MIR } on the Eddington ratio .
These results suggest that a large fraction of the warm dust producing MIR emission in AGNs is likely embedded in polar outflows in the NLR instead of in the torus .