English
Related papers

Related papers: The Lyman-beta forest as a cosmic thermometer

200 papers

Using a suite of hydrodynamical simulations with cold dark matter, baryons, and neutrinos, we present a detailed study of the effect of massive neutrinos on the 1-D and 3-D flux power spectra of the Lyman-$\alpha$ (Ly$\alpha$) forest. The…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Christian Pedersen , Andreu Font-Ribera , Thomas D. Kitching , Patrick McDonald , Simeon Bird , Anže Slosar , Keir K. Rogers , Andrew Pontzen

High-resolution hydrodynamics simulations of the Ly-alpha forest in cold dark matter dominated cosmologies appear to predict line widths that are substantially narrower than those observed. Here we point out that Compton heating of the…

Astrophysics · Physics 2009-10-31 Piero Madau , George Efstathiou

We investigate Lyman-alpha (Ly$\alpha$) transmission spikes at $5.2 < z < 6.8$ using synthetic quasar spectra from the ``Cosmic Reionization On Computers" simulations. We focus on understanding the relationship between these spikes and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-01 Hanjue Zhu , Nickolay Gnedin , Camille Avestruz

We study the effects of box size on ENZO simulations of the intergalactic medium (IGM) at z = 2. We follow statistics of the cold dark matter (CDM) and the Lya absorption. We find that the larger boxes have fewer pixels with significant…

Astrophysics · Physics 2015-05-13 David Tytler , Pascal Paschos , David Kirkman , Michael L. Norman , Tridivesh Jena

On large scales, the Lyman-$\alpha$ forest provides insights into the expansion history of the Universe, while on small scales, it imposes strict constraints on the growth history, the nature of dark matter, and the sum of neutrino masses.…

The Lyman-$\alpha$ forest refers to the series of absorption features observed in the spectra of distant quasars that are produced by neutral hydrogen in the intergalactic medium. Observed over a wide range of redshifts with both ground-…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-22 Jonás Chaves-Montero

We have considered the prospects for measuring the cross Warm Dark Matter (WDM) power spectrum of the redshifted HI 21-cm signal and the Lyman-$\alpha$ forest and thereby constraining WDM mass using observations with upcoming…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Anjan Kumar Sarkar , Ashis Kumar Pal , Tapomoy Guha Sarkar

Lyman-alpha forest lines in QSO spectra have typical widths of 20-50 km/s. Low column density absorbers in cosmological simulations are large, diffuse structures, and the Hubble flow across the spatially extended absorber is usually the…

Astrophysics · Physics 2007-05-23 David H. Weinberg , Lars Hernquist , Neal Katz , Rupert Croft , Jordi Miralda-Escudé

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

At low densities the standard ionisation history of the intergalactic medium (IGM) predicts a decreasing temperature of the IGM with decreasing density once hydrogen (and helium) reionisation is complete. Heating the high-redshift,…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 A. Rorai , G. D. Becker , M. G. Haehnelt , R. F. Carswell , J. S. Bolton , S. Cristiani , V. D'Odorico , G. Cupani , P. Barai , F. Calura , T. -S. Kim , E. Pomante , E. Tescari , M. Viel

Cosmological studies of the Lyman-Alpha (Lya) forest typically constrain parameters using two-point statistics. However, higher-order statistics, such as the three-point function (or its Fourier counterpart, the bispectrum) offer additional…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Roger de Belsunce , James M. Sullivan , Patrick McDonald

We investigate the properties of Damped Lyman-alpha systems (DLAs) using high-resolution and large box-size cosmological hydrodynamical simulations of a LambdaCDM model. The numerical code used is a modification of GADGET-2 with a self…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Edoardo Tescari , Matteo Viel , Luca Tornatore , Stefano Borgani

We investigate the nature of correlations in the small-scale flux statistics of the Lyman-$\alpha$ (Ly$\alpha$) forest across redshift bins. Understanding these correlations is important for unbiased cosmological and astrophysical parameter…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-13 Bhaskar Arya , Aseem Paranjape , Tirthankar Roy Choudhury

We present new constraints on the scale dependence of the primordial power spectrum by combining Planck, ACT DR6, SPT-3G and eBOSS Lyman-$\alpha$ forest data, extending sensitivity to smaller comoving scales. While ACT results previously…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-04 Malcolm Fairbairn , Lucien Heurtier , María Olalla Olea-Romacho

The distribution of absorption lines in the spectra of distant quasars, called the Lyman-$\alpha$ (Ly-$\alpha$) forest, is a unique probe of cosmology and the intergalactic medium at high redshifts and small scales. The statistical power of…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Roger de Belsunce , Mikhail M. Ivanov , James M. Sullivan , Kazuyuki Akitsu , Shi-Fan Chen

We present a new perturbative approach to "constrained Ly$\alpha$ radiative transfer'" (RT) through the circum- and inter-galactic medium (CGM and IGM). We constrain the HI content and kinematics of the CGM and IGM in a physically motivated…

Astrophysics of Galaxies · Physics 2018-08-22 Koki Kakiichi , Mark Dijkstra

We undertake the first comprehensive and quantitative real-space analysis of the cosmological information content in the environments of the cosmic web (voids, filaments, walls, and nodes) up to non-linear scales, $k = 0.5$ $h$/Mpc. Relying…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-25 Tony Bonnaire , Nabila Aghanim , Joseph Kuruvilla , Aurélien Decelle

A formalism is presented that allows cosmological experiments to be tested for consistency, and allows a simple frequentist interpretation of the resulting significance levels. As an example of an application, this formalism is used to…

Astrophysics · Physics 2009-10-07 Max Tegmark , Emory Bunn , Wayne Hu

Combining the visibilities measured by an interferometer to form a cosmological power spectrum is a complicated process. In a delay-based analysis, the mapping between instrumental and cosmological space is not a one-to-one relation.…

‹ Prev 1 8 9 10 Next ›