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Related papers: Gas Accretion via Lyman Limit Systems

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The chemical enrichment in the interstellar medium (ISM) of galaxies is regulated by several physical processes: stellar evolution, grain formation and destruction, galactic inflows and outflows. Understanding such processes is essential to…

Astrophysics of Galaxies · Physics 2020-09-30 Ambra Nanni , Denis Burgarella , Patrice Theulé , Benoit Côté , Hiroyuki Hirashita

Measurements of Zn and Cr abundances in damped Lyman alpha systems at absorption redshifts between 0.692 and 3.390 show that metals and dust are much less abundant in high redshift galaxies than in the Milky Way today. We conclude that the…

Astrophysics · Physics 2009-10-28 Max Pettini , David L King , Linda J Smith , Richard W Hunstead

We study the distribution and kinematics of the cool circumgalactic medium (CGM) of emission line galaxies (ELGs) traced by metal absorption lines. Using about 200,000 ELGs from SDSS-IV eBOSS and half a million background quasars from SDSS,…

Astrophysics of Galaxies · Physics 2018-10-17 Ting-Wen Lan , Houjun Mo

We analyze basic properties of about 200 metal systems observed in high resolution spectra of 9 quasars by Boksenberg, Sargent & Rauch (2003). The measured Doppler parameters for the hydrogen and carbon lines are found to be different by a…

Astrophysics · Physics 2007-12-24 M. Demiański , A. G. Doroshkevich

(abridged) We present 8.2m VLT spectroscopic observations of 28 HII regions in 16 emission-line galaxies and 3.6m ESO telescope spectroscopic observations of 38 HII regions in 28 emission-line galaxies. These emission-line galaxies were…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-30 N. G. Guseva , P. Papaderos , H. T. Meyer , Y. I. Izotov , K. J. Fricke

One key piece of information missing from high redshift galaxy surveys is the galaxies' cold gas contents. We present a new method to indirectly determine cold gas surface densities and integrated gas masses from galaxy star formation rates…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 G. Popping , K. I. Caputi , R. S. Somerville , S. C. Trager

With the installation of the Cosmic Origins Spectrograph on the Hubble Space Telescope, measurements of the metal content of the low redshift intergalactic medium (IGM) are now available. Using a new grid-based model for diffuse gas coupled…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Genevieve M. Shattow , Darren J. Croton , Antonio Bibiano

We present evidence that the cosmological mean metallicity of neutral atomic hydrogen gas shows a sudden decrease at z>4.7 down to <Z>=-2.03(+0.09-0.11), which is 6 sigma deviant from that predicted by a linear fit to the data at lower…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Marc Rafelski , Marcel Neeleman , Michele Fumagalli , Arthur M. Wolfe , J. Xavier Prochaska

[Abridged] We investigate how a range of physical processes affect the cosmic metal distribution using a suite of cosmological, hydrodynamical simulations. Focusing on z = 0 and 2, we study the metallicities and metal mass fractions for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Robert P. C. Wiersma , Joop Schaye , Tom Theuns

We use cosmological SPH simulations to study the kinematic signatures of cool gas accretion onto a pair of well-resolved galaxy halos. Cold-flow streams and gas-rich mergers produce a circum-galactic component of cool gas that generally…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-30 Kyle R. Stewart , Tobias Kaufmann , James S. Bullock , Elizabeth J. Barton , Ariyeh H. Maller , Jürg Diemand , James Wadsley

We present an analysis of the gas-phase mass-metallicity relationship (MZR) and fundamental metallicity relationship (FMR) for $65$ star-forming galaxies at $2 < z < 8$ from the JWST/EXCELS survey. We calculate gas-phase metallicities (12 +…

The evolution of the metal content of the universe can be tracked through rest-frame UV spectroscopy of damped Ly-$\alpha$ systems (DLAs). Gas-phase abundances in DLAs must be corrected for dust depletion effects, which can be accomplished…

The gas-phase and stellar metallicities have proven to be important parameters to constrain the star formation history of galaxies. However, HII regions associated with recent star-formation may not have abundances typical for the galaxy as…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Celine Peroux , Varsha P. Kulkarni , Donald G. York

The size, mass, luminosity, and space density of Lyman-alpha emitting (LAE) galaxies observed at intermediate to high redshift agree with expectations for the properties of galaxies that formed metal-poor halo globular clusters (GCs). The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Bruce G. Elmegreen , Sangeeta Malhotra , James Rhoads

We examine the temperature history of gas accreted by forming galaxies in SPH simulations. About half the gas shock heats to roughly the virial temperature of the galaxy potential well before cooling, condensing, and forming stars, but the…

Astrophysics · Physics 2008-11-26 Dusan Keres , Neal Katz , David H. Weinberg , Romeel Dave

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…

Despite advances in observational data, theoretical models, and computational techniques to simulate key physical processes in the formation and evolution of galaxies, the stellar mass assembly of galaxies still remains an unsolved problem…

We measure the oxygen metallicity of the ionized gas along the major axis of seven dwarf star-forming galaxies. Two of them, SDSSJ1647+21 and SDSSJ2238+14, show 0.5 dex metallicity decrements in inner regions with enhanced star-formation…

Astrophysics of Galaxies · Physics 2015-06-18 J. Sanchez Almeida , A. B. Morales-Luis , C. Munoz-Tunon , D. M. Elmegreen , B. G. Elmegreen , J. Mendez-Abreu

A scenario is explored in which Lyman alpha absorbers at low redshift arise from lines of sight through extended galaxy disks, including those of dwarf and low surface brightness galaxies. A population of galaxies is simulated based upon…

Astrophysics · Physics 2009-10-30 Suzanne M. Linder

The cycling of metals between interstellar gas and dust is a critical aspect of the baryon cycle of galaxies, yet our understanding of this process is limited. This study focuses on understanding dust depletion effects in the low…

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