Related papers: AGN Feedback Efficiency of NAL Quasars
Quasar feedback in the form of powerful outflows is invoked as a key mechanism to quench star formation in galaxies, preventing massive galaxies to over-grow and producing the red colors of ellipticals. On the other hand, some models are…
We present an observational study of 22 broad absorption line quasars (BAL QSOs) at $3\lesssim z \lesssim5$ based on optical/near-IR spectroscopy, aiming to investigate quasar winds and their effects. The near-IR spectroscopy covers the…
Quasar outflows carry mass, momentum and energy into the surrounding environment, and have long been considered a potential key factor in regulating the growth of supermassive black holes and the evolution of their host galaxies. A crucial…
The Hubble Space Telescope/Cosmic Origins Spectrograph (COS) has opened a new discovery space for studying quasar absorption outflows and their contribution to AGN feedback. Specifically, COS provides high-quality far-ultraviolet (FUV)…
To explain the properties of the local galaxy population, theoretical models require active galactic nuclei (AGN) to inject energy into host galaxies, thereby expelling outflows of gas that would otherwise form stars. Observational tests of…
Associated absorption lines (AALs) in quasar spectra are valuable probes of the gas kinematics and physical conditions in quasar environments. The host galaxies are by definition in an active evolution stage that might involve large-scale…
Background quasars are potentially sensitive probes of galactic outflows provided that one can determine the origin of the absorbing material since both gaseous disks and strong bipolar outflows can contribute to the absorption…
Quasar outflows are fundamental components of quasar environments that might play an important role in feedback to galaxy evolution. We report on the emergence of a remarkable new outflow absorption-line system in the quasar PG1411+442…
The energy released by active galactic nuclei (AGNs) is considered to have a profound impact on the cold gas properties of their host galaxies, potentially heating or removing the gas and further suppressing star formation. To understand…
We present a detailed analysis of the X-ray emission of HS 1700+6416, a high redshift (z=2.7348), luminous quasar, classified as a Narrow Absorption Line (NAL) quasar on the basis of its SDSS spectrum. The source has been observed 9 times…
We present near-infrared spectra of young radio quasars [P(1.4GHz) ~ 26-27 W/Hz] selected from the Wide-Field Infrared Survey Explorer. The detected objects have typical redshifts of z ~ 1.6-2.5 and bolometric luminosities ~ 10^47 erg/s.…
Outflows from active galactic nuclei (AGN) are often invoked to explain the co-evolution of AGN and their host galaxies, and the scaling relations between the central black hole mass and the bulge velocity dispersion. Nuclear winds are…
AGN-driven outflows are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super massive black holes and their host galaxies. This work aims to detect the…
In the course of a large intervening MgII survey of 25 quasars, the CIV emission lines of six (three radio-loud and three radio-quiet) were observed serendipitously. In four of these six quasars, we detected associated narrow absorption…
Some fraction of narrow absorption lines are physically associated to the quasar/host-galaxy materials (i.e., intrinsic NALs) like those of BALs and mini-BALs. The relation between these three types of absorption lines has not been…
We present observations of ionized gas outflows in eleven z$ =1.39-2.59$ radio-loud quasar host galaxies. Data was taken with the integral field spectrograph (IFS) OSIRIS and the adaptive optics system at the W.M. Keck Observatory targeting…
Approximately 20% of quasi-stellar objects (QSOs) exhibit broad, blue-shifted absorption lines in their ultraviolet spectra. Such features provide clear evidence for significant outflows from these systems, most likely in the form of…
The prevalence and properties of kiloparsec-scale outflows in nearby Type 1 quasars have been the subject of little previous attention. This work presents Gemini integral field spectroscopy of ten Type 1 radio-quiet quasars at $z<0.3$. The…
Winds outflowing from Active Galactic Nuclei (AGNs) may carry significant amount of mass and energy out to their host galaxies. In this paper we report the detection of a sub-relativistic outflow observed in the Narrow Line Seyfert 1 Galaxy…
Using the radio observations by FIRST and NVSS, we build a sample of 151 radio variable quasars selected from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3). Six (probably another two) among them are classified as broad absorption…