AKARI INFRARED CAMERA OBSERVATIONS OF THE 3.3 μm PAH FEATURE IN Swift/BAT AGNs

다국어 초록 (Multilingual Abstract)

Using the InfraRed Camera (IRC) on board the infrared astronomical satellite {\sl AKARI} we study the 3.3 $\mu$mpolycyclic aromatic hydrocarbon (PAH) feature and its connection to active galactic nucleus (AGN) propertiesfor a sample of 54 hard X-­ray selected bright AGN, including both Seyfert 1 and Seyfert 2 type objects.
The sample is selected from the 9-­month {\sl Swift}/BAT survey in the 14--­195 keV band and all of the sources have known neutralhydrogen column densities ($N_{\rm H}$). The 3.3 $\mu$m PAH luminosity ($L_{\rm 3.3{\mu}m}$) is used as a proxy for star-formation (SF)activity and hard X-ray luminosity ($L_{\rm 14-195keV}$) as an indicator of the AGN power. We explore for possible difference of SFactivity between type 1 (un-absorbed) and type 2 (absorbed) AGN. We use several statistical analyses taking the upper-limits of thePAH lines into account utilizing survival analysis methods. The results of our $\log(L_{\rm 14-195keV})$ versus $\log(L_{\rm 3.3{\mu}m})$regression shows a positive correlation and the slope for the type 1/unobscured AGN is steeper than that of type 2/obscured AGN at a$3\sigma$ level. Also our analysis shows that the circum-nuclear SF is more enhanced in type 2/absorbed AGN than type1/un-absorbed AGN for low $L_{\rm 14-195keV}$ luminosity/low Eddington ratio AGN, while there is no significant dependence of SF activityon the AGN type in the high $L_{\rm 14-195keV}$ luminosities/Eddington ratios.

참고문헌 (Reference)

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