The Low-Redshift Lyα Forest in Cold Dark Matter Cosmologies

  title={The Low-Redshift Ly$\alpha$ Forest in Cold Dark Matter Cosmologies},
  author={Romeel Dav{\'e} and Lars Hernquist and Neal Katz and David H. Weinberg},
  journal={The Astrophysical Journal},
We study the physical origin of the low-redshift Lyα forest in hydrodynamic simulations of four cosmological models, all variants of the cold dark matter scenario. Our most important conclusions are insensitive to the cosmological model, but they depend on our assumption that the UV background declines at low redshift in concert with the declining population of quasar sources. We find that the expansion of the universe drives rapid evolution of dN/dz (the number of absorbers per unit redshift… 
High-Redshift Galaxies in Cold Dark Matter Models
We use hydrodynamic cosmological simulations to predict the star formation properties of high-redshift galaxies (z = 2-6) in five variants of the inflationary cold dark matter scenario, paying
High-Redshift Galaxies and the Lyα Forest in a Cold Dark Matter Universe
We use a cosmological hydrodynamic simulation of a cold dark matter universe to investigate theoretically the relationship between high-redshift galaxies and the Lyα forest at redshift z = 3.
The Baryon Cycle at High Redshifts: Effects of Galactic Winds on Galaxy Evolution in Overdense and Average Regions
We employ high-resolution cosmological zoom-in simulations focusing on a high-sigma peak and an average cosmological field at $z\sim 6-12$, in order to investigate the influence of environment and
The Influence of Ωb on High-Redshift Structure
We analyze high-redshift structure in three hydrodynamic simulations that have identical initial conditions and cosmological parameters and differ only in the value of the baryon density parameter,
Lyman Break Galaxies and the Lyα Forest
We use hydrodynamic cosmological simulations to predict correlations between Lyα forest absorption and the galaxy distribution at redshift z ≈ 3. The probability distribution function (PDF) of Lyα
Distribution of Damped Lyα Absorbers in a Λ Cold Dark Matter Universe
We present the results of a numerical study of a galactic wind model and its implications on the properties of damped Lyα absorbers (DLAs) using cosmological hydrodynamic simulations. We vary both
Large-scale mass distribution in the Illustris simulation
Observations at low redshifts thus far fail to account for all of the baryons expected in the Universe according to cosmological constraints. A large fraction of the baryons presumably resides in a
Extended Lyα Emission from Interacting Galaxies at High Redshifts
Recent observations have discovered a population of extended Lyα sources, dubbed Lyα blobs (LABs), at high redshift z � 2 6.6. These LABs typically have a luminosity of L � 10 42 10 44 erg s −1 , and
The Statistical and Physical Properties of the Low-Redshift Lyα Forest Observed with the Hubble Space Telescope/STIS*
We examine the Lyα absorber population at z < 0.3 detected in spectra of the quasars PG 0953+415 and H1821+643 taken with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope.
Cooling Radiation and the Lyα Luminosity of Forming Galaxies
We examine the cooling radiation from forming galaxies in hydrodynamic simulations of the LCDM model (cold dark matter with a cosmological constant), focusing on the Ly? line luminosities of


The Clustering of High-Redshift Galaxies in the Cold Dark Matter Scenario
We investigate the clustering of high-redshift galaxies in five variants of the cold dark matter (CDM) scenario, using hydrodynamic cosmological simulations that resolve the formation of systems with
Damped Lyα Absorber at High Redshift: Large Disks or Galactic Building Blocks?
We investigate the nature of the physical structures giving rise to damped Lyα absorption systems (DLAS) at high redshift. In particular, we examine the suggestion that rapidly rotating large disks
The Lyman alpha forest in the cold dark matter model
Cosmological simulations with gas provide a detailed description of the intergalactic medium, which makes possible predictions of neutral hydrogen absorption in the spectra of background QSOs. We
The Population of Damped Lyα and Lyman Limit Systems in the Cold Dark Matter Model
Lyman limit and damped Lyα absorption systems probe the distribution of collapsed, cold gas at high redshift. Numerical simulations that incorporate gravity and gasdynamics can predict the abundance
A Lower Bound on the Cosmic Baryon Density
We derive lower bounds on the cosmic baryon density from the requirement that the high-redshift intergalactic medium (IGM) contain enough neutral hydrogen to produce the observed Lyα absorption in
Evolution of Structure in the Intergalactic Medium and the Nature of the Lyα Forest
We have performed a detailed statistical study of the evolution of structure in a photoionized intergalactic medium (IGM) using analytical simulations to extend the calculation into the mildly
Spectral Analysis of the Lyα Forest in a Cold Dark Matter Cosmology
We simulate the Lyα forest in a standard cold dark matter universe using a two-level hierarchical grid code to evolve the dark and baryonic matter components self-consistently. We solve the
The Redshift Evolution of the Ly alpha Forest
We have analyzed the properties of low column density Lyman alpha forest clouds (12.8 < log N_HI < 16.0) toward 5 QSOs at different redshifts, using high signal-to-noise data from the HIRES
Probing the Universe with the Ly α forest — II. The column density distribution
I apply the well controlled hydro-PM (HPM) approximation of Gnedin &38; Hui to model the column density distribution of the Ly α forest for 25 different flat cosmological scenarios, including
Contribution of Galaxies to the Background Hydrogen-Ionizing Flux
ABSTRACT We estimate the evolution of the contribution of galaxies to the cosmic backgroundflux at 912˚A by means of a semi-analytic model of galaxy formation and ev olution.Such a modelling has been