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Related papers: Column Density Profiles of Cold Clouds Driven by G…

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We present Far Ultraviolet Spectroscopic Explorer and Hubble Space Telescope observations of high, intermediate, and low ion absorption in high-velocity cloud Complex C along the lines of sight toward five active galaxies. Our purpose is to…

Galactic outflows are known to consist of several gas phases, however, so far the connection between these multiple phases has been investigated little and only in a few objects. In this paper, we analyse MUSE/VLT data of 26 local (U)LIRGs…

We re-analyze the HST high resolution spectroscopic data of the intrinsic absorber in NGC 5548 and find that the C IV absorption column density is at least four times larger than previously determined. This increase arises from accounting…

Astrophysics · Physics 2009-11-06 Nahum Arav , Martijn de Kool , Kirk T. Korista

We compare X-ray and UV spectroscopic observations of NGC 5548. Both data sets show O VI absorption troughs associated with the AGN outflow from this galaxy. We find that the robust lower limit on the column density of the O VI X-ray trough…

We present the equivalent width and column density measurements for low and intermediate ionization states of the circumgalactic medium (CGM) surrounding 44 low-z, L ~ L* galaxies drawn from the COS-Halos survey. These measurements are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jessica Werk , J. Xavier Prochaska , Christopher Thom , Jason Tumlinson , Todd Tripp , John O'Meara , Molly Peeples

Aims: We systematically explore a plausible subset of the parameter space involving effective temperatures and metallicities of the ionizing stellar sources, the effects of the hardening of their radiation by surrounding leaky HII regions…

Astrophysics of Galaxies · Physics 2019-02-13 J. A. Weber , A. W. A. Pauldrach , T. L. Hoffmann

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…

Outflows are believed to be ubiquitous and fundamentally important in active galaxies. Despite their importance, key physical properties of outflows remain poorly unconstrained; this severely limits study of the acceleration process. It is…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-02 Karen M. Leighly , Adrian B. Lucy , Matthias Dietrich , Donald Terndrup , Sarah C. Gallagher

We present a study of the properties of the transition temperature (T~10^5 K) gas in the Milky Way corona, based on measurements of OVI, NV, CIV, SiIV and FeIII absorption lines seen in the far ultraviolet spectra of 58 sightlines to…

Astrophysics of Galaxies · Physics 2015-06-04 Bart P. Wakker , Blair D. Savage , Andrew J. Fox , Robert A. Benjamin

With the advent of Chandra and XMM, X-ray lines spectroscopy of AGN outflows is off to an exciting start. In this paper we illuminate some of the complications involved in extracting the outflow's physical conditions (ionization…

Astrophysics · Physics 2007-05-23 Nahum Arav

We present model calculations of ionization fractions for elements in the warm (log T = 4), low-density photoionized interstellar medium (WIM) of the Milky Way. We model the WIM as a combination of overlapping low-excitation H II regions…

Using deep JWST/NIRSpec spectra from the Blue Jay survey, we perform the first systematic investigation of neutral gas content in massive galaxies at Cosmic Noon based on the Ca II H, K absorption lines. We analyze a sample of 9 galaxies at…

We develop a new method to constrain the physical conditions in the cool (~10^4 K) circumgalactic medium (CGM) from measurements of ionic column densities, by assuming that the cool CGM spans a large range of gas densities and that small…

Astrophysics of Galaxies · Physics 2016-10-26 Jonathan Stern , Joseph F. Hennawi , J. Xavier Prochaska , Jessica K. Werk

I provide an observational review of the properties of starburst-driven galactic superwinds, focusing mainly on recent results pertinent to the transport of metals and energy into the IGM. Absorption-line studies are providing rich…

Astrophysics · Physics 2007-05-23 D. K. Strickland

Galactic-scale outflows are a crucial component of galaxy evolution, yet their properties in the early universe remain poorly constrained. We present the first statistical investigation of \ion{Mg}{2}-traced cool gas outflows in galaxies…

Astrophysics of Galaxies · Physics 2026-02-25 Cheqiu Lyu , Haoran Yu , Enci Wang , Junxian Wang , Cheng Jia , Jie Song , Yangyao Chen , Jinyang Wang , Zeyu Chen , Chengyu Ma , Yifan Wang , Xu Kong

We report the first ensemble results from the FUSE survey of molecular hydrogen in lines of sight with A_V $\gtrsim$ 1 mag. We have developed techniques for fitting computed profiles to the low-J lines of H2, and thus determining column…

Many of the baryons associated with a galaxy reside in its circumgalactic medium (CGM), in a diffuse volume-filling phase at roughly the virial temperature. Much of the oxygen produced over cosmic time by the galaxy's stars also ends up…

Astrophysics of Galaxies · Physics 2019-08-14 G. M. Voit

We present modeling to explore the conditions of the broad-line emitting gas in two extreme Narrow-line Seyfert 1 galaxies, using the observational results described in the first paper of this series. Photoionization modeling using Cloudy…

Astrophysics · Physics 2009-11-10 Karen M. Leighly

The processes allowing the escape of ionizing photons from galaxies into the intergalactic medium are poorly known. To understand how Lyman continuum (LyC) photons escape galaxies, we constrain the HI covering fractions and column densities…

Astrophysics of Galaxies · Physics 2018-08-08 Simon Gazagnes , John Chisholm , Daniel Schaerer , Anne Verhamme , Jane R. Rigby , Matthew Bayliss

Molecular hydrogen being unobservable in cold molecular clouds, the column density measurements of molecular gas currently rely either on dust emission observation in the far-IR or on star counting. (Sub-)millimeter observations of numerous…