ﻻ يوجد ملخص باللغة العربية
We explore the relationships between the 3.3 {mu}m polycyclic aromatic hydrocarbon (PAH) feature and active galactic nucleus (AGN) properties of a sample of 54 hard X-ray selected bright AGNs, including both Seyfert 1 and Seyfert 2 type objects, using the InfraRed Camera (IRC) on board the infrared astronomical satellite AKARI. The sample is selected from the 9-month Swift/BAT survey in the 14-195 keV band and all of them have measured X-ray spectra at $E lesssim 10$ keV. These X-ray spectra provide measurements of the neutral hydrogen column density ($N_{rm H}$) towards the AGNs. We use the 3.3 {mu}m PAH luminosity ($L_{rm 3.3{mu}m}$) as a proxy for star formation activity and hard X-ray luminosity ($L_{rm 14-195keV}$) as an indicator of the AGN activity. We search for possible difference of star-formation activity between type 1 (un-absorbed) and type 2 (absorbed) AGNs. We have made several statistical analyses taking the upper-limits of the PAH 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 AGNs is steeper than that of type 2/obscured AGNs at a $3sigma$ level. Also our analysis show that the circum-nuclear star-formation is more enhanced in type 2/absorbed AGNs than type 1/un-absorbed AGNs for low X-ray luminosity/low Eddington ratio AGNs, while there is no significant dependence of star-formation activities on the AGN type in the high X-ray luminosities/Eddington ratios.
Aims. The aim of this work is to further investigate the nature of PAH excitation and emission especially in the context of tracing star formation in a variety of extragalactic environments. Here we turn our attention to the energetic environment of
We first obtained the spectrum of the diffuse Galactic light (DGL) at general interstellar space in 1.8-5.3 um wavelength region with the low-resolution prism spectroscopy mode of the AKARI Infra-Red Camera (IRC) NIR channel. The 3.3 um PAH band is d
We examine the self-consistency of laboratory and observational data for potential carriers of the 3.3 $mu$m infrared emission feature (IEF), a member of the ubiquitous family of strong interstellar IEFs at 3.3, 3.4, 6.2, 7.7, 8.6, 11.2, and 12.7 $mu
We present results of the 2.5-5 {mu}m spectroscopy of a sample of hard X-ray selected active galactic nuclei (AGNs) using the grism mode of the InfraRed Camera (IRC) on board the infrared astronomical satellite AKARI. The sample is selected from the
Local infrared (IR) luminosity functions (LFs) are necessary benchmarks for high-redshift IR galaxy evolution studies. Any accurate IR LF evolution studies require accordingly accurate local IR LFs. We present infrared galaxy LFs at redshifts redshif