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Related papers: Characterizing the Low-Redshift Intergalactic Medi…

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We list and analyze H I absorption lines at redshifts 2 < z < 4 with column density (12 < log(N_HI) < 19) in 40 high-resolutional (FWHM = 8.0 km/s) quasar spectra obtained with the Keck+HIRES. We de-blend and fit all H I lines within 1,000…

Astrophysics · Physics 2008-11-26 T. Misawa , D. Tytler , M. Iye , D. Kirkman , N. Suzuki , D. Lubin , N. Kashikawa

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

We have analyzed the properties of metals in the high redshift intergalactic medium using a novel objective pixel optical depth technique on a sample of extremely high signal-to-noise Keck HIRES and ESI spectra of 26 quasars between…

Astrophysics · Physics 2008-11-26 Antoinette Songaila

We present a search for metal absorption line systems at the highest redshifts to date using a deep (30h) VLT/X-Shooter spectrum of the z = 7.084 quasi-stellar object (QSO) ULAS J1120+0641. We detect seven intervening systems at z > 5.5,…

Recent STIS and FUSE observations have detected OVI absorption lines at low redshift that are not clearly associated with any galactic system. In this paper, we argue that these lines are due to metal enriched hot gas in the intergalactic…

Astrophysics · Physics 2009-11-07 T. Fang , G. L. Bryan

Using a hydrodynamic simulation of a LCDM universe, we investigate the "X-ray forest" absorption imprinted on the spectra of background quasars by the intervening intergalactic medium (IGM). In agreement with previous studies, we find that…

Astrophysics · Physics 2009-11-07 Xuelei Chen , David H. Weinberg , Neal Katz , Romeel Dave'

Using Voigt-profile-fitting procedures on Keck HIRES spectra of nine QSOs we identify 1099 CIV absorber components clumped in 201 systems outside the Lyman forest over 1.6 < z < 4.4. With associated SiIV, CII, SiII and NV where available we…

Astrophysics of Galaxies · Physics 2015-05-27 Alec Boksenberg , Wallace L. W. Sargent

(Abridged) This paper presents an absorption-line study of the multiphase circumgalactic medium (CGM) based on observations of Lya, CII, CIV, SiII, SiIII, and SiIV absorption transitions in the vicinities of 195 galaxies at redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Cameron Jia Liang , Hsiao-Wen Chen

We study a sample of 17 z>1.5 absorbers selected based on the presence of strong CI absorption lines in SDSS spectra and observed with the ESO-VLT spectrograph X-shooter. We derive metallicities, depletion onto dust, and extinction by dust,…

We report the discovery of a further line of sight allowing detection of HeII Ly alpha absorption by the intergalactic medium. A HST/STIS survey of 32 bright z ~ 3 quasars selected from the Hamburg Quasar Surveys yielded one detection…

Astrophysics · Physics 2016-08-30 D. Reimers , C. Fechner , H. -J. Hagen , P. Jakobsen , D. Tytler , D. Kirkman

We present new far-ultraviolet spectra from the Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 1ES1553+113 covering the wavelength range 1135-1795 A. The data show a smooth continuum with a wealth of narrow absorption features…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-19 Charles W. Danforth , Brian A. Keeney , John T. Stocke , J. Michael Shull , Yangsen Yao

Low ionization metal absorption due to OI has been identified as an important probe of the physical state of the inter-/circumgalactic medium at the tail-end of reionization. We use here high-resolution hydrodynamic simulations to interpret…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Laura C. Keating , Martin G. Haehnelt , George D. Becker , James S. Bolton

We present a tomographic analysis of metal absorption lines arising from the circumgalactic medium (CGM) of galaxies at z~0.5-2, using Multi Unit Spectroscopic Explorer (MUSE) observations of two background quasars at z~2.2 and 2.8, which…

Astrophysics of Galaxies · Physics 2024-01-09 Rajeshwari Dutta , Ana Acebron , Michele Fumagalli , Claudio Grillo , Gabriel B. Caminha , Matteo Fossati

High resolution optical (HIRES/Keck) and UV (STIS/HST) spectra, covering a large range of chemical transitions, are analyzed for three single-cloud weak MgII absorption systems along the line of sight toward the quasar PG 1634+706. Weak…

Astrophysics · Physics 2008-11-26 J. C. Charlton , J. Ding , S. G. Zonak , C. W. Churchill , N. A. Bond , J. R. Rigby

The extraordinarily bright quasar PHL 1811 at a redshift z = 0.192 provides an attractive opportunity to use ultraviolet absorption-line spectroscopy to study the properties of gas systems in the local universe. An R = 20,000 far-UV…

We present a high spectral resolution optical spectrum of the bright quasar Q~1037-2704. The large number of absorption systems suggests the presence of an intervening supercluster, but the issue remains controversial.\par We demonstrate…

Astrophysics · Physics 2007-05-23 Yannick Lespine , Patrick Petitjean

We describe a survey for OVI absorption in the spectra of 5 high redshift quasars (2.2 < z < 2.8). We identify 12 cosmological systems, and 6 systems that are either ejected from the background QSO or affected by its local radiation field.…

Astrophysics · Physics 2009-11-07 Robert A. Simcoe , Wallace L. W. Sargent , Michael Rauch

We present an ultraviolet spectroscopic survey of strong H I absorbers in the intergalactic medium, probing their evolution over the last 6-7 Gyr at redshifts $0.24 \leq z \leq 0.84$. We measure column densities $N_{\rm HI} \,( {\rm…

Astrophysics of Galaxies · Physics 2017-11-15 J. Michael Shull , Charles W. Danforth , Evan M. Tilton , Joshua Moloney , Matthew L. Stevans

We present high-resolution UV spectra of absorption-line systems toward the low-z QSO HS0624+6907 (z=0.3700). Coupled with spectroscopic galaxy redshifts, we find that many of these absorbers are integalactic gas clouds distributed within…

We present a spectroscopic and imaging analysis of the $z_{gal} \approx 1.1334$ ultra-strong MgII absorption system identified in the $VLT$/UVES spectrum of a background quasar located at $\rho \approx 18$ kpc from a star-forming galaxy.…

Astrophysics of Galaxies · Physics 2025-12-11 Purvi Udhwani , Sameer , Anand Narayanan , Sowgat Muzahid , Jane Charlton , Sebastiano Cantalupo
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