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تسجيل مستخدم جديدBlack Hole and Galaxy Coevolution in Moderately Luminous Active Galactic Nuclei at z~1.4 in SXDF
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We investigate the relation of black hole mass versus host stellar mass and that of mass accretion rate versus star formation rate (SFR) in moderately luminous ($log L_{rm bol} sim 44.5-46.5 {rm erg s^{-1}}$), X-ray selected broad-line active galactic nuclei (AGNs) at $z=1.18-1.68$ in the Subaru/XMM-Newton Deep Field. The far-infrared to far-ultraviolet spectral energy distributions of 85 AGNs are reproduced with the latest version of Code Investigating GALaxy Emission ({tt CIGALE}), where the AGN clumpy torus model {tt SKIRTOR} is implemented. Most of their hosts are confirmed to be main-sequence star-forming galaxies. We find that the mean ratio of the black hole mass ($M_{rm BH}$) to the total stellar mass ($M_{rm stellar}$) is $log M_{rm BH}/M_{rm stellar} = -2.2$, which is similar to the local black hole-to-bulge mass ratio. This suggests that if the host galaxies of these moderately luminous AGNs at $zsim1.4$ are dominated by bulges, they already established the local black hole mass-bulge mass relation; if they are disk dominant, their black holes are overmassive relative to the bulges. AGN bolometric luminosities and SFR show a good correlation with ratios higher than that expected from the local black hole-to-bulge mass relation, suggesting that these AGNs are in a SMBH-growth dominant phase.
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