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Related papers: The Last Eight-Billion Years of Intergalactic SiIV…

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We surveyed the HST UV spectra of 49 low-redshift quasars for z < 1 CIV candidates, relying solely on the characteristic wavelength separation of the doublet. After consideration of the defining traits of CIV doublets (e.g., consistent line…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Kathy L. Cooksey , Christopher Thom , J. Xavier Prochaska , Hsiao-Wen Chen

We have investigated the distribution and evolution of ~3100 intergalactic HI absorbers with HI column densities log N(HI) = [12.75, 17.0] at 1.9 < z < 3.2, using 18 high resolution, high S/N quasar spectra obtained from the ESO VLT/UVES…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Tae-Sun Kim , Adrian M. Partl , Robert F. Carswell , Volker Müller

We have vastly increased the CIV statistics at intermediate redshift by surveying the thousands of quasars in the Sloan Digital Sky Survey Data-Release 7. We visually verified over 16,000 CIV systems with 1.46 < z < 4.55---a sample size…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Kathy L. Cooksey , Melodie M. Kao , Robert A. Simcoe , John M. O'Meara , J. Xavier Prochaska

We use 29 z>4 quasar spectra to build a homogeneous sample of high-redshift CIV absorbers. We use these data to calculate the number density, n(z), of W_rest(CIV)>0.30 A CIV doublets. We find that n(z) increases with time from z ~ 4.5. In…

Astrophysics · Physics 2009-11-10 Celine Peroux , Patrick Petitjean , Bastien Aracil , Mike Irwin , Richard McMahon

We present further results of a survey for absorption line systems in the spectra of four high redshift quasars (5.79 $\le$ z$_{\textrm{em}}$ $\le$ 6.13) obtained with the ESO Very Large Telescope X-Shooter. We identify 36 $\textrm{CIV}$…

We present the largest catalog to date of triply ionized carbon (CIV) absorbers detected in quasar spectra from the Dark Energy Spectroscopic Instrument. Using an automated matched-kernel convolution method with adaptive signal-to-noise…

We investigate the abundance and distribution of metals in the high-redshift intergalactic medium and circum-galactic medium through the analysis of a sample of almost 600 SiIV absorption lines detected in high and intermediate resolution…

We present a large high-resolution study of the distribution and evolution of CIV absorbers, including the weakest population with equivalent widths $W_r<0.3$~{\AA}. By searching 369 high-resolution, high signal-to-noise spectra of quasars…

In Keck HIRES spectra of 9 QSOs we identify a sample of 908 CIV absorber components in 188 systems outside the Lyman forest in the redshift range 1.6 < z < 4.4, with related lines of SiIV, CII, SiII and NV. The properties of the CIV…

Astrophysics · Physics 2007-05-23 Alec Boksenberg , Wallace L. W. Sargent , Michael Rauch

Column density distribution functions of CIV with 12.05 < log (N) < 14.35 and SiIV with 11.70 < log (N) < 13.93 have been obtained using 81 CIV absorbers and 35 SiIV absorbers redward of the Ly alpha forest in the lines of sight to seven…

Astrophysics · Physics 2009-10-30 Antoinette Songaila

We have performed an analysis of over 34,000 MgII doublets at 0.36 < z < 2.29 in Sloan Digital Sky Survey (SDSS) Data-Release 7 quasar spectra; the catalog, advanced data products, and tools for analysis are publicly available. The catalog…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-20 Eduardo N. Seyffert , Kathy L. Cooksey , Robert A. Simcoe , John M. O'Meara , Melodie M. Kao , J. Xavier Prochaska

To investigate the evolution of metal-enriched gas over recent cosmic epochs as well as to characterize the diffuse, ionized, metal-enriched circumgalactic medium (CGM), we have conducted a blind survey for C IV absorption systems in 89 QSO…

We report the discovery of a strong CIV 1548,1550 absorption system at z_abs = 5.7238 in the near-infrared spectrum (J-band) of the z_em = 6.28 QSO SDSS J1030+0524. These observations, obtained with the Infrared Spectrometer And Array…

Astrophysics · Physics 2009-11-11 Emma V. Ryan-Weber , Max Pettini , Piero Madau

We study metal line absorption of CIV, CII, SiIV, and NV at redshifts z=3.5 to z=2 within the framework of a cosmological model for the Lyman alpha forest, comparing the results of numerical simulations to recent observations by Songaila &…

Astrophysics · Physics 2009-10-30 Uffe Hellsten , Romeel Dave , Lars Hernquist , David H. Weinberg , Neal Katz

We present the results of observations taken with the X-shooter spectrograph devoted to the study of quasars at z ~ 6. This paper focuses on the properties of metals at high redshift traced, in particular, by the C IV doublet absorption…

We report on the highly variable SiIV and CIV broad absorption lines in SDSS J113831.4+351725.2 across four observational epochs. Using the SiIV doublet components, we find that the blue component is usually saturated and non-black, with…

Astrophysics of Galaxies · Physics 2015-03-03 Conor Wildy , Michael R. Goad , James T. Allen

Absorption-line spectroscopy of 23 background QSOs and numerous background galaxies has let us measure the spatial distribution of metals and neutral hydrogen around 1044 UV-selected galaxies at redshifts 1.8<z<3.3. The typical galaxy is…

Astrophysics · Physics 2008-11-26 K. L. Adelberger , A. E. Shapley , C. C. Steidel , M. Pettini , D. K. Erb , N. A. Reddy

We present a sample of 46 [OIII]-emitting galaxies at z<0.8 detected in the fibre spectra of quasars from the SDSS-DR7 through an automatic search procedure. We also detect [OII] and Hb emission lines from most of these galaxies in the SDSS…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 P. Noterdaeme , R. Srianand , V. Mohan

We test the galactic outflow model by probing associated galaxies of four strong intergalactic CIV absorbers at $z=5$--6 using the Hubble Space Telescope (HST) ACS ramp narrowband filters. The four strong CIV absorbers reside at $z=5.74$,…

Astrophysics of Galaxies · Physics 2017-11-01 Zheng Cai , Xiaohui Fan , Romeel Dave , Kristian Finlator , Ben Oppenheimer

Intervening CIV absorbers are key tracers of metal-enriched gas in galaxy halos over cosmic time. Previous studies suggest that the CIV cosmic mass density ($\Omega_{\rm CIV}$) decreases slowly over 1.5 $\lesssim z\lesssim$ 5 before…

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