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Cosmic photons can be efficiently collected by broadband intensity mapping but information on their emission redshift and frequency is largely lost. We introduce a technique to statistically recover these otherwise collapsed dimensions by…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-12 Yi-Kuan Chiang , Brice Ménard , David Schiminovich

We present an analysis of the absorption-line system in the Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph spectrum at a redshift of $z_{\rm a}={3.1448}$ associated with the quasar SDSS J122040.23+092326.96, whose…

Astrophysics of Galaxies · Physics 2025-01-03 Qiguo Tian , Lei Hao , Yipeng Zhou , Xiheng Shi , Tuo Ji , Peng Jiang , Lin Lin , Zhenya Zheng , Hongyan Zhou

We characterize the properties of the intergalactic medium (IGM) around a sample of galaxies extracted from state-of-the-art hydrodynamical simulations of structure formation in a cosmological volume of 25 Mpc comoving at $z\sim 2$. The…

Astrophysics of Galaxies · Physics 2018-07-03 C. Mongardi , M. Viel , V. D'Odorico , T. -S. Kim , P. Barai , G. Murante , P. Monaco

Determining when and how the first galaxies reionized the intergalactic medium (IGM) promises to shed light on both the nature of the first objects and the cosmic history of baryons. Towards this goal, quasar absorption lines play a unique…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 George D. Becker , James S. Bolton , Adam Lidz

We present a theoretical study of transient absorption and reshaping of extreme ultraviolet (XUV) pulses by helium atoms dressed with a moderately strong infrared (IR) laser field. We formulate the atomic response using both the…

Atomic Physics · Physics 2013-03-25 Mette B. Gaarde , Christian Buth , Jennifer L. Tate , Kenneth J. Schafer

We present an absorption line analysis of the Lyman limit system (LLS) at z=3.55 in our Magellan/MIKE spectrum of PKS2000-330. Our analysis of the Lyman limit and full HI Lyman series constrains the total HI column density of the LLS (N_HI…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Gabriel E. Prochter , J. Xavier Prochaska , John M. O'Meara , Scott Burles , Rebecca A. Bernstein

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

Astrophysics · Physics 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We examine the absorption line spectra of a sample of 31 luminous (M_UV=-23) Lyman break galaxies at redshift z~6 using data taken with the FOCAS and OSIRIS spectrographs on the Subaru and GTC telescopes. For two of these sources we present…

Astrophysics of Galaxies · Physics 2020-10-28 Yuichi Harikane , Nicolas Laporte , Richard S. Ellis , Yoshiki Matsuoka

We present very deep WFPC2 images and FOS spectroscopy from the Hubble Space Telescope (HST) together with numerous supporting ground-based observations of the field of the quasar 3C 336 ($z_{em}=0.927$). The observations are designed to…

Astrophysics · Physics 2016-08-30 C. Steidel , M. Dickinson , D. Meyer , K. Adelberger , K. Sembach

We measured metallicities for 33 z=3.4-4.2 absorption line systems drawn from a sample of H I-selected-Lyman limit systems (LLSs) identified in Sloan Digital Sky Survey (SDSS) quasar spectra and stratified based on metal line features. We…

Astrophysics of Galaxies · Physics 2017-01-09 Ana Glidden , Thomas J. Cooper , Kathy L. Cooksey , Robert A. Simcoe , John M. O'Meara

We used HIRES/Keck profiles (R=6 km/s) of MgII and FeII in combination with FOS/HST spectra (R=230 km/s) to place constraints on the physical conditions (metallicities, ionization conditions, and multi-phase distribution) of absorbing gas…

Astrophysics · Physics 2009-10-30 Christopher W. Churchill , Jane C. Charlton

We study the distribution and evolution of highly ionised intergalactic metals in the Evolution and Assembly of Galaxies and their Environment (EAGLE) cosmological, hydrodynamical simulations. EAGLE has been shown to reproduce a wide range…

Astrophysics of Galaxies · Physics 2016-03-16 Alireza Rahmati , Joop Schaye , Robert A. Crain , Benjamin D. Oppenheimer , Matthieu Schaller , Tom Theuns

Absorption-line spectroscopy is a powerful tool used to estimate element abundances in the nearby as well as distant universe. The accuracy of the abundances thus derived is, naturally, limited by the accuracy of the atomic data assumed for…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Romas Kisielius , Varsha P. Kulkarni , Gary J. Ferland , Pavel Bogdanovich , Matt L. Lykins

We present an investigation of MgII absorbers characterized as single-cloud weak systems at z~1. We measured column densities and Doppler parameters for MgII and FeII in 15 systems found in HIRES/Keck spectra at 6.6 km/s. Using these…

Astrophysics · Physics 2016-08-30 Jane R. Rigby , Jane C. Charlton , Christopher W. Churchill

We present the far-UV spectrum of the quasar HS1700+6416 taken with FUSE. This QSO provides the second line of sight with the HeII absorption resolved into a Ly alpha forest structure. Since HS1700+6416 is slightly less redshifted (z=2.72)…

We present an extended analysis of the high dispersion IUE spectra of SN 1993J in M81, based on the improved data in the IUE final archive. Eight interstellar absorption components can be identified in the velocity range from -200 km/s to…

Astrophysics · Physics 2007-05-23 Ole Marggraf , Klaas S. de Boer

The chemical composition of high redshift galaxies is an important property which gives clues to their past history and future evolution and yet is difficult to measure with current techniques. In this paper we investigate new metallicity…

In this paper, we present spectrophotometric models for galaxies of different morphological type whose spectral energy distributions (SEDs) take into account the effect of dust in absorbing UV-optical light and re-emitting it in the…

Astrophysics · Physics 2009-11-11 Lorenzo Piovan , Rosaria Tantalo , Cesare Chiosi

We use a sample of 332 Hubble Space Telescope spectra of 184 QSOs with z > 0.33 to study the typical ultraviolet spectral properties of QSOs, with emphasis on the ionizing continuum. Our sample is nearly twice as large as that of Zheng et…

Astrophysics · Physics 2016-08-30 R. C. Telfer , W. Zheng , G. A. Kriss , A. F. Davidsen

We present a detailed model for the ionized absorbing gas evident in the 900 ksec Chandra HETGS spectrum of NGC 3783. The analysis was carried out with PHASE a new tool designed to model X-ray and UV absorption features in ionized plasmas.…

Astrophysics · Physics 2009-11-10 Y. Krongold , F. Nicastro , N. S. Brickhouse , M. Elvis , D. A. Liedahl , S. Mathur
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