We apply a new X-ray clumpy torus model called XCLUMPY \citep Tanimoto2019a , where the clump distribution is assumed to be the same as in the infrared clumpy torus model ( CLUMPY ) by \citet Nenkova2008a , Nenkova2008b , to the broadband X-ray spectra of type-1 active galactic nuclei ( AGNs ) for the first time .
We analyze the archival data of IC 4329A and NGC 7469 observed with NuSTAR / Suzaku and NuSTAR / XMM-Newton , respectively , whose infrared spectra were studied with CLUMPY by \citet Ichikawa2015 and optical extinctions ( A _ { V } ) of the tori were estimated .
We consider two models , invoking ( Model 1 ) a relativistic reflection component from the accretion disk and ( Model 2 ) a partial absorber .
Assuming that the narrow Fe K \alpha emission line at 6.4 keV originates from the torus , we separate the contribution of the torus reflection components in the total spectra .
Our models yield equatorial hydrogen column densities of the tori to be N ^ { Equ } _ { H } = ( 0.53–1.43 ) \times 10 ^ { 23 } ~ { } cm ^ { -2 } and N ^ { Equ } _ { H } = ( 0.84–1.43 ) \times 10 ^ { 24 } ~ { } cm ^ { -2 } , for IC 4329A and NGC 7469 , respectively .
We find that the N _ { H } / A _ { V } ratios in the tori are by factors of 25–68 ( IC 4329A ) and 2.4–3.9 ( NGC 7469 ) smaller than that in the Galactic interstellar medium ( ISM ) .
These results suggest that a non-negligible fraction of AGNs are “ dust-rich ” compared with the Galactic ISM , as opposite to the general trend previously reported in many obscured AGNs .