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We investigate the dependence of gas kinematics and column densities in the MgII-absorbing circumgalactic medium on galaxy color, azimuthal angle, and inclination to trace baryon cycle processes. Our sample of 30 foreground isolated…

Astrophysics of Galaxies · Physics 2015-10-14 Nikole M. Nielsen , Christopher W. Churchill , Glenn G. Kacprzak , Michael T. Murphy , Jessica L. Evans

The actual mechanism(s) powering galactic outflows in active galactic nuclei (AGN) is still a matter of debate. At least two physical models have been considered in the literature: wind shocks and radiation pressure on dust. Here we provide…

Astrophysics of Galaxies · Physics 2021-02-10 W. Ishibashi , A. C. Fabian , N. Arakawa

We present high spectral resolution VLT observations of the BAL quasar SDSS J0318-0600. This high quality data set allows us to extract accurate ionic column densities and determine an electron number density of n_e=10^3.3 +/- 0.2 cm^-3 for…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Jay P. Dunn , Manuel A. Bautista , Nahum Arav , Maxwell Moe , Kirk T. Korista , Elisa Costantini , Chris Benn , Sara Ellison , Doug Edmonds

Galactic outflows commonly contain multiphase gas, and its physical origin requires explanation. Using the CGOLS (Cholla Galactic OutfLow Simulations) suite of high-resolution isolated galaxy models, we demonstrate the viability of rapid…

Astrophysics of Galaxies · Physics 2018-08-09 Evan E. Schneider , Brant E. Robertson , Todd A. Thompson

Galactic outflows are thought to eject baryons back out to the circum-galactic medium (CGM). Studies based on metal absorption lines (MgII in particular) in the spectra of background quasars indicate that the gas is ejected anisotropically,…

X-ray absorption and emission lines now serve as powerful diagnostics of the outflows from active galaxies. Detailed X-ray line studies of outflows have recently been enabled for a significant number of active galaxies via the grating…

Astrophysics · Physics 2009-11-07 W. N. Brandt , S. Kaspi

The connection between X-ray weakness and powerful X-ray outflows is both expected in a scenario where outflows are connected with radiation-driven winds, and observed in several sources, both in the local Universe and at high redshift.…

Astrophysics of Galaxies · Physics 2024-11-20 Bartolomeo Trefoloni

We present a study of a luminous, z=0.15, type-2 quasar (log [L([OIII])/(erg/s)]=42.8) from the Quasar Feedback Survey. It is classified as 'radio-quiet' (log [L(1.4 GHz)/(W/Hz)]=23.8); however, radio imaging reveals ~1 kpc low-power jets…

We examine how HI and metal absorption lines within low-redshift galaxy halos trace the dynamical state of circumgalactic gas, using cosmological hydrodynamic simulations that include a well-vetted heuristic model for galactic outflows. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Amanda Brady Ford , Romeel Davé , Benjamin D. Oppenheimer , Neal Katz , Juna A. Kollmeier , Robert Thompson , David H. Weinberg

James Webb Space Telescope opens a new window to directly probe luminous quasars powered by billion solar mass black holes in the epoch of reionization and their co-evolution with massive galaxies with unprecedented details. In this paper,…

We investigate the extent and the properties of the MgII cool, low-density absorbing gas located in the halo and in the circum-galactic environment of quasars, using a sample of 31 projected quasar pairs with impact parameter pd<200kpc in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 E. P. Farina , R. Falomo , R. Scarpa , R. Decarli , A. Treves , J. K. Kotilainen

We assume a distribution of clouds optically thick for electron scattering (OTCM) which are moderately optically thin for absorption and we consider them as a model of the mean quasar spectrum of Laor et al. (1997). We show that the model…

Astrophysics · Physics 2007-05-23 B. Czerny , A. -M. Dumont

We present Keck/LRIS spectroscopy of seven isolated galaxy-quasar pairs at $0.4 \leq z \leq 0.6$, each exhibiting ultra-strong MgII absorption ($W_{r,2796} \geq 3$ {\AA}), probing both down-the-barrel and transverse gas flows.…

(Abridged) With the goal of investigating the nature of OVI absorbers at high redshifts, we study the effects of proximity to the background quasar. In a sample of sixteen quasars at z(QSO) between 2.14 and 2.87 observed at 6.6 km/s…

Astrophysics · Physics 2009-11-13 Andrew J. Fox , Jacqueline Bergeron , Patrick Petitjean

Narrow-Line Seyfert 1 (NLS1) Galaxies are an important type of active galactic nucleus (AGN), generally expected to be accreting at high Eddington rate. The properties of their outflows and importance of AGN feedback remain intriguing. We…

Astrophysics of Galaxies · Physics 2023-01-18 Xiao-Dan Fu , Junfeng Wang , Xiaoyu Xu , Zhi-Xiang Zhang

SDSS J072910.34+333634.3 is a reddened quasar at z=0.96. The archivel Keck/ESI spectrum and our new P200/TripleSpec spectrum reveal an absorption line system in He I*, Ca II H\&K and Na ID. The absorption line system has a width of…

Astrophysics of Galaxies · Physics 2016-12-19 Tong Liu , Luming Sun , Xiang Pan , Hongyan Zhou

Feedback likely plays a vital role in the formation of dwarf galaxies. While stellar processes have long been considered the main source of feedback, recent studies have revealed tantalizing signs of AGN feedback in dwarf galaxies. In this…

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. The variability of BALs can help us understand the structure,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Paola Rodríguez Hidalgo , Tom A. Barlow

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…

It has been suggested that non-relativistic outflows from quasars can naturally account for the missing component of the extragalactic $\gamma$-ray background and explain the cumulative neutrino background through pion decay in collisions…

High Energy Astrophysical Phenomena · Physics 2017-03-15 Xiawei Wang , Abraham Loeb
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