English
Related papers

Related papers: The nature of NV absorbers at high redshift

200 papers

We present a comprehensive catalog of ultraviolet HST/STIS and FUSE absorbers in the low-redshift IGM at z<0.4. The catalog draws from the extensive literature on IGM absorption, and it reconciles discrepancies among previous catalogs…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Evan M. Tilton , Charles W. Danforth , J. Michael Shull , Teresa L. Ross

We present a new approach to constrain the spectral energy distribution of the intergalactic UV background observationally by studying metal absorption systems. We study single-component metal line systems exhibiting various well-measured…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Cora Fechner

We briefly review the use of UV absorption lines in the spectra of low-redshift QSOs for the study of the physical conditions, metallicity, and baryonic content of the low-z IGM, with emphasis on the missing baryons problem. Current results…

We analyse high-resolution VLT+UVES spectra of the low-ionization intrinsic absorber observed in the BAL QSO SDSS J001130.56+005550.7. Two narrow absorption systems at velocities -600 km/s and -22000 km/s are detected. The low-velocity…

Astrophysics · Physics 2009-11-10 D. Hutsemekers , P. B. Hall , J. Brinkmann

We report on the detection of a population of weak metal-line absorbers in the halo or nearby intergalactic environment of the Milky Way. Using high-resolution ultraviolet absorption-line spectra of bright QSOs obtained with the Space…

Astrophysics of Galaxies · Physics 2014-11-18 Philipp Richter , Jane C. Charlton , Alessio P. M. Fangano , Nadya Ben Bekhti , Joseph R. Masiero

In this work, we present new calculations of the observables associated with synthetic metal and HI absorption lines in the spectra of high redshift quasars, inspired by questions and limitations raised in work with a uniform Haardt-Madau…

Astrophysics of Galaxies · Physics 2020-04-08 L. A. García , E. V. Ryan-Weber

We have studied the abundance of oxygen in the IGM by analyzing OVI, CIV, SiIV, and HI pixel optical depths derived from a set of high-quality VLT and Keck spectra of 17 QSOs at 2.1 < z < 3.6. Comparing OVI and CIV optical depth ratios to…

Astrophysics · Physics 2009-11-13 Anthony Aguirre , Corey Dow-Hygelund , Joop Schaye , Tom Theuns

We present HST/STIS and FUSE spectra of the quasar RXJ1230.8+0115 (V=14.4, z=0.117). In addition to Galactic, Virgo, and intervening absorption, this quasar is host to a remarkable intrinsic absorption complex. Four narrow absorption line…

Astrophysics · Physics 2009-11-10 Rajib Ganguly , Joseph Masiero , Jane C. Charlton , Kenneth R. Sembach

New measurements of the z~6 intergalactic CIV abundance are presented, using moderate resolution IR spectra of two QSOs taken with GNIRS on Gemini South. These data were systematically searched for high redshift CIV absorption lines, using…

Astrophysics · Physics 2008-11-26 Robert A. Simcoe

We present a study of the intrinsic absorption lines in the ultraviolet spectra of Seyfert 1 galaxies. We find that the fraction of Seyfert 1 galaxies that show absorption associated with their active nuclei is more than one-half (10/17),…

We present a detailed analysis of a high resolution spectrum of the damped Ly$\alpha$ system at $z_{\rm abs}$~=~2.8112toward PKS~0528-250. The absorption redshift is slightly larger than the emission redshift of the quasar. We estimate the…

Astrophysics · Physics 2007-05-23 R. Srianand , P. Petitjean

We present an extragalactic HI 21-cm absorption lines catalog from a blind search at z $\leqslant$ 0.35, using drift-scan data collected in 1325.6 hours by the ongoing Commensal Radio Astronomy FasT Survey (CRAFTS) and FAST All Sky HI…

We use observations of spatially-aligned C II, C IV, Si II, Si IV, and O I absorbers to probe the slope and intensity of the ultraviolet background (UVB) at $z \sim 6$. We accomplish this by comparing observations with predictions from a…

Astrophysics of Galaxies · Physics 2018-01-22 Caitlin Doughty , Kristian Finlator , Benjamin D. Oppenheimer , Romeel Davé , Erik Zackrisson

Detailed Monte Carlo Inversion analysis of the spectral lines from three Lyman limit systems (LLS) [N(HI) > 10^{17} cm^-2] and nine lower N(HI) systems [2 10^{14} < N(HI) < 2 10^{16} cm^-2] observed in the VLT/UVES spectra of Q0347-3819 (in…

Results of a careful analysis of the highly ionized absorption systems, observed over the redshift range 2.198--2.2215 in the zem=2.24 HDFS-QSO J2233-606, are presented. Strong OVI and NeVIII absorptions are detected. Most of the lines show…

Astrophysics · Physics 2011-05-23 Patrick Petitjean , R. Srianand

We present the Voigt profile (VP) models, column densities, Doppler b parameters, kinematics, and distribution of components for 422 MgII absorbers found in a survey of 249 HIRES and UVES quasar spectra. The equivalent width range of the…

We continue our series of papers on intergalactic medium (IGM) tracers using quasi-stellar objects (QSOs), having examined gamma-ray bursts (GRBs) and blazars in earlier studies. We have estimated the IGM properties of hydrogen column…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 Tony Dalton , Simon L. Morris , Michele Fumagalli , Efrain Gatuzz

We use high-quality, medium-resolution {\it Hubble Space Telescope}/Cosmic Origins Spectrograph (\HST/COS) observations of 82 UV-bright AGN at redshifts $z_{AGN}<0.85$ to construct the largest survey of the low-redshift intergalactic medium…

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,…

In this paper, we extend our works of Papers I and II, which are assigned to systematically survey \CIVab\ narrow absorption lines (NALs) with \zabs$\ll$\zem\ on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS), to…

Astrophysics of Galaxies · Physics 2016-09-28 Chen Zhi-fu , Gu Qiu-sheng , Zhou Luwenjia , Chen Yanmei