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Related papers: Constraining the Fluctuating Gunn-Peterson Approxi…

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We examine the statistics of the low-redshift Lyman-alpha forest from smoothed particle hydrodynamic simulations in light of recent improvements in the estimated evolution of the cosmic ultraviolet background (UVB) and recent observations…

High-redshift QSO spectra show large spatial fluctuations in the Ly-alpha opacity of the intergalactic medium on surprisingly large scales at z>~5.5. We present a radiative transfer simulation of cosmic reionization driven by galaxies that…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Girish Kulkarni , Laura C. Keating , Martin G. Haehnelt , Sarah E. I. Bosman , Ewald Puchwein , Jonathan Chardin , Dominique Aubert

In order to carry out a systematic and thorough measurement of the HI Gunn-Peterson effect at high redshift, a quantitatively testable and repeatable procedure, in particular, a robust statistical weighting technique, is developed. It is…

Astrophysics · Physics 2009-10-22 Yihu Fang , Arlin Crotts

The Lyman-$\alpha$ (hereafter Ly-$\alpha$) forest is a probe of large-scale matter density fluctuations at high redshift, $z > 2.1$. It consists of HI absorption spectra along individual lines-of-sight. If the line-of-sight density is large…

We describe techniques for comparing spectra extracted from cosmological simulations and observational data, using the same methodology to link Lyman-alpha properties derived from the simulations with properties derived from observational…

Astrophysics · Physics 2009-11-07 C. E. Petry , C. D. Impey , N. Katz , D. H. Weinberg , L. E. Hernquist

Density fluctuations in the matter distribution lead to distortions of the images of distant galaxies through weak gravitational lensing effects. This provides an efficient probe of the cosmological parameters and of the density field. In…

Astrophysics · Physics 2007-05-23 P. Valageas

The Lyman-$\alpha$ forest offers a unique avenue for studying the distribution of matter in the high redshift universe and extracting precise constraints on the nature of dark matter, neutrino masses, and other $\Lambda$CDM extensions.…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-29 Laura Cabayol-Garcia , Jonás Chaves-Montero , Andreu Font-Ribera , Christian Pedersen

Our understanding of the Lyman-$\alpha$ forest has received a great boost with the advent of the Keck Telescope and large 3D hydrodynamical simulations. We present new simulations using the SPH technique with a P^3MG (Particle-Particle…

Astrophysics · Physics 2007-05-23 J. W. Wadsley , J. Richard Bond

We study the effects of AGN feedback on the Lyman-$\alpha$ forest 1D flux power spectrum (P1D). Using the Simba cosmological-hydrodynamic simulations, we examine the impact that adding different AGN feedback modes has on the predicted P1D.…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-26 Megan Taylor Tillman , Blakesley Burkhart , Stephanie Tonnesen , Simeon Bird , Greg L. Bryan

In this Letter we explore a version of the test of cosmological geometry proposed by Alcock and Paczynski (1979), using observations of the Lyman-alpha forest in the spectra of close quasar pairs. By comparing the correlations in absorption…

Astrophysics · Physics 2009-10-30 Lam Hui , Albert Stebbins , Scott Burles

The ultralight dark photon is a well-motivated, hypothetical dark matter candidate. In a dilute plasma, they can resonantly convert into photons, and heat up the intergalactic medium between galaxies. In this work, we explore the dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-04 Andrea Trost , James S. Bolton , Andrea Caputo , Hongwan Liu , Stefano Cristiani , Matteo Viel

We have measured the transmission of the Lyman alpha forest produced by neutral hydrogen scattering in the intergalactic medium between redshifts 2 and 6.3 using high signal to noise, high resolution (R > 5000) observations of 50 quasars…

Astrophysics · Physics 2011-05-05 Antoinette Songaila

If a significant fraction of the dark matter in the Universe is made of an ultra-light scalar field, named fuzzy dark matter (FDM) with a mass $m_a$ of the order of $10^{-22}-10^{-21}$ eV, then its de Broglie wavelength is large enough to…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-22 Eric Armengaud , Nathalie Palanque-Delabrouille , Christophe Yèche , David J. E. Marsh , Julien Baur

We present the first characterization of the Gunn-Peterson trough in high-redshift galaxies using public JWST NIRSpec spectroscopy. This enables us to derive the first galaxy-based IGM opacity measurements at the end of reionisation. Using…

Astrophysics of Galaxies · Physics 2025-09-03 Romain A. Meyer , Guido Roberts-Borsani , Pascal Oesch , Richard S. Ellis

We investigate the large-scale inhomogeneities of the hydrogen ionizing radiation field in the Universe at redshift z=3. Using a raytracing algorithm, we simulate a model in which quasars are the dominant sources of radiation. We make use…

Astrophysics · Physics 2009-11-10 Rupert A. C. Croft

The evolution of the expansion rate of the Universe results in a drift in the redshift of distant sources over time. A measurement of this drift would provide us with a direct probe of expansion history. The Lyman alpha forest has been…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Madhura Killedar , Geraint F. Lewis

Ly-$\alpha$ tomography surveys have begun to produce three-dimensional (3D) maps of the intergalactic medium (IGM) opacity at $z \sim 2.5$ with Mpc resolution. These surveys provide an exciting new way to discover and characterize…

Astrophysics of Galaxies · Physics 2022-05-14 Mahdi Qezlou , Andrew B. Newman , Gwen C. Rudie , Simeon Bird

The forest of Lyman-alpha absorption lines seen in the spectra of distant quasars has become an important probe of the distribution of matter in the Universe. We use large, hydrodynamical simulations from the OWLS project to investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Matteo Viel , Joop Schaye , Craig M. Booth

The decline in abundance of Lyman-$\alpha$ (Ly$\alpha$) emitting galaxies at $z \gtrsim 6$ is a powerful and commonly used probe to constrain the progress of cosmic reionization. We use the CoDaII simulation, which is a radiation…

The thermal history and structure of the intergalactic medium (IGM) at $z \geq 4$ is an important boundary condition for reionization, and a key input for studies using the Ly$\alpha$ forest to constrain the masses of alternative dark…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Christopher Cain , Evan Scannapieco , Matthew McQuinn , Anson D'Aloisio , Hy Trac
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