English
Related papers

Related papers: Cosmology with the Lyman-alpha Forest

200 papers

We present the Lyman-$\alpha$ flux power spectrum measurements of the XQ-100 sample of quasar spectra obtained in the context of the European Southern Observatory Large Programme "Quasars and their absorption lines: a legacy survey of the…

Absorption lines in the Lyman-alpha forest can be thought of as peaks in neutral hydrogen density along lines of sight. The column density distribution (the number density of absorption lines as a function of column density) is then a…

Astrophysics · Physics 2007-05-23 Lam Hui , Nickolay Y. Gnedin , Yu Zhang

Cosmological hydrodynamic simulations can accurately predict the properties of the intergalactic medium (IGM), but only under the condition of retaining high spatial resolution necessary to resolve density fluctuations in the IGM. This…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Daniele Sorini , José Oñorbe , Zarija Lukić , Joseph F. Hennawi

We investigate Lyman-alpha forest flux statistics in mixed fuzzy dark matter (FDM) and cold dark matter (CDM) cosmologies using the Fluctuating Gunn-Peterson Approximation (FGPA) applied to hybrid Schr\"odinger-Poisson and N-body…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Yourong Frank Wang

Evidence for a positive cosmological constant $\Lambda$, derived from the Ly$\alpha$-forest in high-resolution spectra of quasars, leads to a closed, low-density, $\Lambda$-dominated universe. The analysis is based on the assumption of a…

Astrophysics · Physics 2007-05-23 Carsten van de Bruck , Wolfgang Priester

We present a study of 7 star-forming galaxies from the Cosmic Evolution Survey (COSMOS) observed with the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST). The galaxies are located at relatively low redshifts,…

We perform an analysis of the full shapes of Lyman-$\alpha$ (Ly$\alpha$) forest correlation functions measured from the first data release (DR1) of the Dark Energy Spectroscopic Instrument (DESI). Our analysis focuses on measuring the…

The forest of Lyman-$\alpha$ absorption lines detected in the spectra of distant quasars encodes information on the nature and properties of dark matter and the thermodynamics of diffuse baryonic material. Its main observable -- the 1D flux…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-19 Bruno Villasenor , Brant Robertson , Piero Madau , Evan Schneider

We discuss the feasibility of measuring the cosmological metric using the redshift space correlation function of the Lya forest in multiple lines of sight, as a function of angular and velocity separation. The geometric parameter that is…

Astrophysics · Physics 2009-10-30 Patrick McDonald , Jordi Miralda-Escude

We investigate the clustering properties of 13 QSO lines of sight in flat space, with average redshifts from z~2 to 4. We estimate the 1-D power spectrum and the integral density of neighbours, and discuss their variation with respect to…

Astrophysics · Physics 2009-10-31 Luca Amendola , Sandra Savaglio

We study the distribution of low-redshift Ly$\alpha$ clouds in a CDM model using numerical simulations including photoionization and cooling of the baryonic component. The ionizing background is found to be efficient enough to keep most of…

Astrophysics · Physics 2016-08-30 Patrick Petitjean , Jan P. Mücket , Ron Kates

The z > 2 Lyman-alpha (Lya) forest traces the underlying dark-matter distribution on large scales and, given sufficient sightlines, can be used to create 3D maps of large-scale structure. We examine the observational requirements to…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-23 Khee-Gan Lee , Joseph F. Hennawi , Martin White , Rupert Croft , Melih Ozbek

We make forecasts for the constraining power of the 1D Wavelet Scattering Transform (WST) when used with a Lyman-$\alpha$ forest cosmology survey. Using mock simulations and a Fisher matrix, we show that there is considerable cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-05 Hurum Maksora Tohfa , Simeon Bird , Ming-Feng Ho , Mahdi Qezlou , Martin Fernandez

The quasar in the Hubble Deep Field South (HDFS), J2233-606 (z=2.23) has been exhaustively observed by ground based telescopes and by the STIS spectrograph on board the Hubble Space Telescope at low, medium and high resolution in the…

We directly measure the evolution of the intergalactic Lyman-alpha effective optical depth, tau_eff, over the redshift range 2<z<4.2 from a sample of 86 high-resolution, high-signal-to-noise quasar spectra obtained with Keck/ESI,…

Astrophysics · Physics 2010-11-11 C. -A. Faucher-Giguere , J. X. Prochaska , A. Lidz , L. Hernquist , M. Zaldarriaga

Our goal in this paper is to test some popular dark matter models by Ly-alpha forest in QSO spectra. Recent observations of the size and velocity of Ly-alpha forest clouds have indicated that the Ly-alpha absorption is probably not given by…

Astrophysics · Physics 2009-10-28 Hongguang BI , Jian GE , Li-Zhi FANG

We study the physical origin of the low-redshift Lyman alpha forest in hydrodynamic simulations of four CDM cosmologies. Our main conclusions are insensitive to the cosmological model but depend on our assumption that the UV background…

Astrophysics · Physics 2009-10-26 Romeel Dave' , Lars Hernquist , Neal Katz , David Weinberg

We test estimators of the galaxy power spectrum $P(k)$ against simulated galaxy catalogues constructed from N-body simulations and we derive formulae to correct for biases. These estimators are then applied to compute the power spectrum of…

Astrophysics · Physics 2015-06-24 H. Tadros , G. Efstathiou

We introduce an efficient and accurate alternative to full hydrodynamic simulations, Hydro-PM (HPM), for the study of the low column density Lyman-alpha forest. It consists of a Particle-Mesh solver, modified to compute, in addition to the…

Astrophysics · Physics 2009-10-30 Nickolay Y. Gnedin , Lam Hui

We present an effective field theory (EFT) approach to extract fundamental cosmological parameters from the Lyman-alpha forest flux fluctuations as an alternative to the standard simulation-based techniques. As a first application, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-21 Mikhail M. Ivanov , Michael W. Toomey , Naim Göksel Karaçaylı