摘要
The study ofkiloparsec-scale dual active galactic nuclei （AGN） provides important clues for understanding the co-evolution between host galaxies and their central supermassive black holes undergoing a merging process. We present long-slit spectroscopy of J0038 ＋4128, a kiloparsec-scale dual AGN candidate, discovered recently by Huang et al., using the Yunnan Faint Object Spectrograph and Camera （YFOSC） mounted on the Lijiang 2.4-m telescope administered by Yunnan Observatories. From the long-slit spectra, we find that the average relative line-of-sight （LOS） velocity between the two nuclei （J0038＋4128N and J0038＋4128S） is about 150 km s-1. The LOS velocities of the emission lines from the gas ionized by the nuclei activities and of the absorption lines from stars governed by the host galaxies for different regions of J0038＋4128 exhibit the same trend. The same trend in velocities indicates that the gaseous disks are co-rotating with the stellar disks in this ongoing merging system. We also find several knots/giant H II regions scattered around the two nuclei with strong star formation revealed by the observed line ratios from the spectra. Those regions are also clearly detected in images from HST F336W/U-band and HST F555W/V-band.
The study ofkiloparsec-scale dual active galactic nuclei （AGN） provides important clues for understanding the co-evolution between host galaxies and their central supermassive black holes undergoing a merging process. We present long-slit spectroscopy of J0038 ＋4128, a kiloparsec-scale dual AGN candidate, discovered recently by Huang et al., using the Yunnan Faint Object Spectrograph and Camera （YFOSC） mounted on the Lijiang 2.4-m telescope administered by Yunnan Observatories. From the long-slit spectra, we find that the average relative line-of-sight （LOS） velocity between the two nuclei （J0038＋4128N and J0038＋4128S） is about 150 km s-1. The LOS velocities of the emission lines from the gas ionized by the nuclei activities and of the absorption lines from stars governed by the host galaxies for different regions of J0038＋4128 exhibit the same trend. The same trend in velocities indicates that the gaseous disks are co-rotating with the stellar disks in this ongoing merging system. We also find several knots/giant H II regions scattered around the two nuclei with strong star formation revealed by the observed line ratios from the spectra. Those regions are also clearly detected in images from HST F336W/U-band and HST F555W/V-band.
基金
Funding for the telescope has been provided by CAS
the People’s Government of Yunnan Province
supported by the National Natural Science Foundation of China(Grant Nos.11133006 and 11361140347)
the Strategic Priority Research Program“The Emergence of Cosmological Structures”of the Chinese Academy of Sciences(Grant No.XDB09000000)
support by the National Key Basic Research Program of China(2014CB845700)
