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相关论文: Metallicity of the Intergalactic Medium Using Pixe…

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Very recently a new inversion method has been developped to analyze the intergalactic medium seen in absorption in quasar spectra (the so-called Lyman-alpha forest). This method is applied to recover the temperature of the gas and the…

We publicly release a new sample of $34$ medium resolution quasar spectra at $5.77\leq z_{\rm em}\leq6.54$ observed with the Echellette Spectrograph and Imager (ESI) on the Keck telescope. This quasar sample represents an ideal laboratory…

星系天体物理 · 物理学 2018-09-05 Anna-Christina Eilers , Frederick B. Davies , Joseph F. Hennawi

We present results of a blind survey of Lyman limit systems (LLSs) detected in absorption against 105 quasars at z~3 using the blue sensitive MagE spectrograph at the Magellan Clay telescope. By searching for Lyman limit absorption in the…

宇宙学与河外天体物理 · 物理学 2015-06-16 Michele Fumagalli , John M. O'Meara , J. Xavier Prochaska , Gabor Worseck

In this paper, we present low resolution (R=500) near-infrared spectra for selected and serendipitous sources in six inner in-plane Galactic fields, with the aim of analysing the stellar content present. From the equivalent widths of the…

天体物理学 · 物理学 2009-11-13 C. González-Fernández , A. Cabrera-Lavers , P. L. Hammersley , F. Garzón

We present new ISOCAM mid-infrared spectra of three starbursting nearby dwarf galaxies, NGC1569, IIZw40, NGC1140 and the 30Dor region of the LMC and explore the properties of the ISM in low-metallicity environments, also using additional…

天体物理学 · 物理学 2016-08-30 S. C. Madden , F. Galliano , A. P. Jones , M. Sauvage

Understanding the spatial distribution of metals within galaxies allows us to study the processes of chemical enrichment and mixing in the interstellar medium (ISM). In this work, we map the two-dimensional distribution of metals using a…

We discuss two aspects of the ionization and abundances in QSO intrinsic absorbers. First, we use the high-ionization doublet Ne VIII 770,780 to test the relationship between the UV line absorbers and the ``warm'' absorbers detected in soft…

天体物理学 · 物理学 2008-02-03 F. Hamann , T. Barlow , R. D. Cohen , V. Junkkarinen , E. M. Burbidge

We study the composition of the Galactic interstellar medium (ISM) toward the Galactic center region (5 < |l| < 20 degree) by utilizing X-ray absorption features of three bright low-mass X-ray binaries (LMXBs), GX 13+1, GX 5-1, and GX…

天体物理学 · 物理学 2009-11-10 Yoshihiro Ueda , Kazuhisa Mitsuda , Hiroshi Murakami , Kyoko Matsushita

Aims. This article aims to provide an alternative method of measuring the porosity of multi-phase composite ices from their refractive indices and of characterising how the abundance of a premixed contaminant (e.g., CO2) affects the…

We present Goddard High Resolution Spectrograph and ORFEUS-II measurements of Si IV, CIV, N V, and O VI absorption in the interstellar medium of the Galactic disk and halo toward the nucleus of the Seyfert galaxy ESO141-055. The high…

天体物理学 · 物理学 2009-10-31 Kenneth R. Sembach , Blair D. Savage , Mark Hurwitz

We measure the spatial clustering of metals in the intergalactic medium from z = 1.7 to 3.0, as traced by 643 CIV and 104 SiIV N >= 10^12 cm^-2 absorption systems in 19 high signal-to-noise (40-80) and high resolution (R = 45000) quasar…

We have obtained an exceptionally high S/N, high resolution spectrum of the gravitationally lensed quasar Q1422+231 in order to investigate the metal enrichment of the IGM. A column density distribution function (CDDF) is determined for…

天体物理学 · 物理学 2009-07-09 Sara L. Ellison , Antoinette Songaila , Joop Schaye , Max Pettini

We derive metal abundance estimates for a large sample of starbursting emission-line galaxies (ELGs). Our sample is drawn from the KPNO International Spectroscopic Survey (KISS) which has discovered over 2000 ELG candidates to date.…

天体物理学 · 物理学 2009-10-12 Jason Melbourne , John J. Salzer

We compare the environmental and star formation properties of far-infrared detected and non--far-infrared detected galaxies out to $z \sim0.5$. Using optical spectroscopy and photometry from the Galaxy And Mass Assembly (GAMA) and Sloan…

Chandra high-resolution spectra toward eight low-mass Galactic binaries have been analyzed with a photoionization model that is capable of determining the physical state of the interstellar medium. Particular attention is given to the…

天体物理仪器与方法 · 物理学 2015-06-19 E. Gatuzz , J. García , C. Mendoza , T. R. Kallman , M. A. Bautista , T. W. Gorczyca

To measure the column densities of interstellar and intergalactic gas clouds using absorption line spectroscopy, the apparent optical depth technique (AOD) of Savage & Sembach (1991) can be used instead of a curve-of-growth analysis or…

天体物理学 · 物理学 2008-11-26 Andrew J. Fox , Blair D. Savage , Bart P. Wakker

This paper presents a systematic study of the photoionization and thermodynamic properties of the cool circumgalactic medium (CGM) as traced by rest-frame ultraviolet absorption lines around 26 galaxies at redshift $z\lesssim1$. The study…

(Abridged)The X-ray measurements of the ICM metallicity are becoming more frequent due to the availability of powerful X-ray telescope with excellent spatial and spectral resolutions. The information which can be extracted from the…

天体物理学 · 物理学 2009-11-13 E. Rasia , P. Mazzotta , H. Bourdin , S. Borgani , L. Tornatore , S. Ettori , K. Dolag , L. Moscardini

We investigate the geometric distribution of gas metallicities in the circumgalactic medium (CGM) around $47$, $z<0.7$ galaxies from the "Multiphase Galaxy Halos" Survey. Using a combination of quasar spectra from HST/COS and from…

We present a census of the mass density of metals and their evolution with cosmic time on a global scale throughout the Universe, synthesizing robust estimates of metals in stars, hot intra-cluster gas, and gaseous absorbers tracing neutral…

星系天体物理 · 物理学 2025-07-15 Saloni Deepak , J. Christopher Howk , Nicolas Lehner , Céline Péroux