2018/05/03 by Xinfeng Xu, Nahum Arav, Timothy Miller +2
Physics and Astronomy · #Accretion (finance) #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Eddington luminosity #Electron #Electron density #Galaxies: Formation, Evolution, Phenomena #Galaxy #Geometry #Ion #Ionization #Line (geometry) #Luminosity #Physics #Quasar #Telescope #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/ab164e
published as 2019ApJ...876..105X · 8 pages, 4 figures, 3 tables, submitted to ApJ
arxiv created 2018/05/03 · openalex publication_date 2019/05/08 · arxiv updated 2019/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract We conducted a survey of quasar outflows using the Very Large Telescope/X-Shooter spectrograph. When choosing the 14 broad absorption line (BAL) and mini-BALs comprising this sample, the data did not cover the S iv and S iv * troughs, whose ratio can be used to determine the distance of the outflows from the central source ( R ). Therefore, this “Blind Survey” is unbiased toward a particular distance scale. Out of the eight outflows where R can be measured, six have R > 100 pc (spanning the range 100–4500 pc), one has R > 10 pc, and only one (at R < 40 pc) is compatible with a much smaller R scale. At least two of the outflows have a kinetic luminosity greater than 0.5% of their Eddington luminosity, implying that they are able to provide significant active galactic nucleus (AGN) feedback. The outflows span a range of 0 to −10,000 km s −1 in velocity, total column density between 10 20.1 and 10 22.6 cm −2 , ionization parameter ( ) in the range 0.01–1, and electron number density between 10 3.2 and 10 5.4 cm −3 , with one upper and one lower limit. The results of this survey can be extrapolated to the majority of BAL outflows, implying that most of these outflows are situated far away from the AGN accretion disk, and that a significant portion of them can contribute to AGN feedback processes.