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Related papers: The Low Column Density Lyman-alpha Forest

200 papers

We present constraints on the amplitude and shape of the matter power spectrum and the density of dark matter within the framework of a standard LambdaCDM model. We use a Markov Chain Monte Carlo approach to combine independent measurements…

Astrophysics · Physics 2008-11-26 J. Lesgourgues , M. Viel , M. G. Haehnelt , R. Massey

(Abridged) We investigate the importance of several numerical artifacts such as lack of resolution on spectral properties of the Lyman alpha forest as computed from cosmological hydrodynamic simulations in a standard cold dark matter…

Astrophysics · Physics 2009-10-30 Tom Theuns , Anthony Leonard , George Efstathiou , F. R. Pearce , P. A. Thomas

The Lyman-alpha forest is the large-scale structure probe for which we appear to have modeling control to the highest wavenumbers. This makes the Lyman-alpha forest of great interest for constraining the warmness/fuzziness of dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-27 Bayu Wilson , Vid Iršič , Matthew McQuinn

We compute the cosmic microwave background (CMB) anisotropy in a low-density, flat, cosmological constant, cold dark matter model which is normalized to the two-year COBE DMR sky map. Although conclusions regarding model viability must…

Astrophysics · Physics 2015-06-24 Bharat Ratra , Naoshi Sugiyama

Following Bi & Davidsen (1997), we perform one dimensional semi analytic simulations along the lines of sight to model the intergalactic medium (IGM). Since this procedure is computationally efficient in probing the parameter space -- and…

Astrophysics · Physics 2009-10-31 T. Roy Choudhury , R. Srianand , T. Padmanabhan

We analyze circumgalactic medium (CGM) in a suite of high-resolution cosmological re-simulations of a Milky-Way size galaxy and show that CGM properties are quite sensitive to details of star formation--feedback loop modelling. The…

Astrophysics of Galaxies · Physics 2016-03-09 Cameron J. Liang , Andrey V. Kravtsov , Oscar Agertz

A combined analysis of Cosmic Microwave Background (CMB) and Lyman-a forest data allows to constrain the matter power spectrum from small scales of about 1 Mpc/h all the way to the horizon scale. The long lever arm and complementarity…

Astrophysics · Physics 2009-10-08 Matteo Viel , Martin G. Haehnelt , Antony Lewis

We combine the Ly-alpha forest power spectrum (LYA) from the Sloan Digital Sky Survey (SDSS) and high resolution spectra with cosmic microwave background (CMB) including 3-year WMAP, and supernovae (SN) and galaxy clustering constraints to…

Astrophysics · Physics 2009-11-11 Uros Seljak , Anze Slosar , Patrick McDonald

Cosmological models with a positive cosmological constant and $\Omega_0<1$ have a number of attractive features. A larger Hubble constant, which can be compatible with the recent HST estimate, and a large fraction of baryon density in…

Astrophysics · Physics 2007-05-23 Anatoly Klypin , Joel Primack , Jon Holtzman

The standard $\rm \Lambda$CDM cosmological model predicts that a large amount of diffuse neutral hydrogen distributes in cosmic filaments, which could be mapped through Lyman-alpha (Ly$\alpha$) emission observations. We use the…

Astrophysics of Galaxies · Physics 2025-08-29 Yizhou Liu , Liang Gao , Shihong Liao , Kai Zhu

Full-physics cosmological simulations are powerful tools for studying the formation and evolution of structure in the universe but require extreme computational resources. Here, we train a convolutional neural network to use a cheaper…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-04 Peter Harrington , Mustafa Mustafa , Max Dornfest , Benjamin Horowitz , Zarija Lukić

We study the effect of different feedback prescriptions on the properties of the low redshift ($z\leq1.6$) Ly$\alpha$ forest using a selection of hydrodynamical simulations drawn from the Sherwood simulation suite. The simulations…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Fahad Nasir , James S. Bolton , Matteo Viel , Tae-Sun Kim , Martin G. Haehnelt , Ewald Puchwein , Debora Sijacki

The spectrum of the quasar Q0055-269 ($z=3.66$) has been observed at the resolution of 14 km s$^{-1}$ in the wavelength interval 4750--6300 \AA. We give a list of Lyman$-\alpha$ lines and metal-line systems for which column densities and…

Astrophysics · Physics 2015-06-24 S. Cristiani , S. D'Odorico , A. Fontana , E. Giallongo , S. Savaglio

We present an analytical model for the cosmological accretion of gas onto dark matter halos, based on a similarity solution applicable to spherical systems. Performing simplified radiative transfer, we compute how the accreting gas turns…

Astrophysics of Galaxies · Physics 2020-11-11 Tom Theuns

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

In this work we use models of molecular clouds (MC), and non-LTE radiative transfer calculations, to obtain a theoretical calibration of the relation between LTE 13CO column density and true column density in MCs. The cloud models consist…

Astrophysics · Physics 2008-02-03 Paolo Padoan , Mika Juvela , John Bally , AAke Nordlund

We examine the abundance, clustering and metallicity of Damped Lyman-alpha Absorbers (DLAs) in a suite of hydrodynamic cosmological simulations using the moving mesh code AREPO. We incorporate models of supernova and AGN feedback, as well…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-08 Simeon Bird , Mark Vogelsberger , Martin Haehnelt , Debora Sijacki , Shy Genel , Paul Torrey , Volker Springel , Lars Hernquist

We investigate the metal species associated with the Ly$\alpha$ forest in the eBOSS quasar spectra. Metal absorption lines are revealed in the stacked spectra from cross-correlating the selected Ly$\alpha$ absorbers in the forest and the…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-31 Li Yang , Zheng Zheng , Hélion du Mas des Bourboux , Kyle Dawson , Matthew M. Pieri , Graziano Rossi , Donald P. Schneider , Axel de la Macorra

We derive the distribution of neutral and ionized gas in high redshift clouds which are optically thick to hydrogen ionizing radiation, using published data on Lyman-limit and Damped Lyman-alpha absorption systems in the redshift range 1.75…

Astrophysics · Physics 2009-10-31 Edvige Corbelli , Edwin E. Salpeter , Rino Bandiera

Recently released Planck data favor a lower value of the Hubble constant and a higher value of the fraction matter density in the standard $\Lambda$CDM model, which are discrepant with some of the low-redshift measurements. Within the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-23 Rong-Gen Cai , Zong-Kuan Guo , Bo Tang