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تسجيل مستخدم جديدSpatially Resolved Interstellar Medium and Highly-Excited Dense Molecular Gas in the Most Luminous Quasar at z=6.327
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Among more than 200 quasars known at $zgtrsim6$, only one object, J0100+2802 (z=6.327), was found hosting a $>10^{10}M_odot$ super-massive black hole (SMBH). In order to investigate the host galaxy properties of J0100+2802, we performed multi-band ALMA observations, aiming at mapping the dust continuum, [CII] and CO(6-5) emission lines with sub-kiloparsec scale resolution, as well as detecting high-J CO lines in CO(11-10), CO(10-9), and CO(7-6). The galaxy size is measured to be $R_{rm major}=3.6pm0.2$ kpc from the high resolution continuum observations. No ordered motion on kilo-parsec scales was found in both [CII] and CO(6-5) emissions. The velocity dispersion is measured to be 161$pm$7 km s$^{-1}$, $sim$3 times smaller than that estimated from the local M-$sigma$ relation. In addition, we found that the CO emission is more concentrate (a factor of 1.8$pm$0.4) than the [CII] emission. Together with CO(2-1) detected by VLA, we measured the CO Spectral Line Energy Distribution (SLED), which is best fit by a two-components model, including a cool component at $sim24$ K with a density of $n_{rm (H_2)}$=10$^{4.5}$ cm$^{-3}$, and a warm component at $sim224$ K with a density of $n_{rm (H_2)}$=10$^{3.6}$ cm$^{-3}$. We also fitted the dust continuum with a graybody model, which indicates that it has either a high dust emissivity $betagtrsim2$ or a hot dust temperature $T_{rm dust}gtrsim60$ K, or a combination of both factors. The highly excited CO emission and hot dust temperature suggest that the powerful AGN in J0100+2802 could contribute to the gas and dust heating although future observations are needed to confirm this.
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