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相关论文: Towards physics responsible for large-scale Lyman-…

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Measurements of the cosmological density parameter Omega using techniques that exploit the gravity-induced motions of galaxies constrain, in linear perturbation theory, the degenerate parameter combination beta = Omega^{0.6}/b, where the…

天体物理学 · 物理学 2011-08-23 Andreas A. Berlind , Vijay K. Narayanan , David H. Weinberg

We present results from end-to-end simulations of observations designed to constrain the rate of change in the expansion history of the Universe using the redshift drift of the Lyman-$\alpha$ forest absorption lines along the lines-of-sight…

宇宙学与河外天体物理 · 物理学 2022-07-19 Chenxing Dong , Anthony Gonzalez , Stephen Eikenberry , Sarik Jeram , Manunya Likamonsavad , Jochen Liske , Deno Stelter , Amanda Townsend

We introduce to astrophysics the threshold probability functions S_2, C_2, and D_2 first derived by \citet{torq+88}, which effectively samples the flux probability distribution (PDF) of the Lya forest at different spatial scales. These…

宇宙学与河外天体物理 · 物理学 2011-10-04 Khee-Gan Lee , David N. Spergel

The full-shape correlations of the Lyman alpha (Ly$\alpha$) forest contain a wealth of cosmological information through the Alcock-Paczy\'{n}ski effect. However, these measurements are challenging to model without robustly testing and…

We present an analytical description of the probability distribution function (PDF) of the smoothed three-dimensional matter density field for modified gravity and dark energy. Our approach, based on the principles of Large Deviations…

宇宙学与河外天体物理 · 物理学 2022-04-05 Matteo Cataneo , Cora Uhlemann , Christian Arnold , Alex Gough , Baojiu Li , Catherine Heymans

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…

We compare the improved measurement of the Lya forest flux probability distribution at 1.7<z<3.2 presented by Kim et al. (2007) to a large set of hydrodynamical simulations of the Lya forest with different cosmological parameters and…

天体物理学 · 物理学 2009-11-13 J. S. Bolton , M. Viel , T. -S. Kim , M. G. Haehnelt , R. F. Carswell

The filamentary network of intergalactic medium (IGM) gas that gives origin to the Lyman-alpha forest in the spectra of distant quasars encodes information on the physics of structure formation and the early thermodynamics of diffuse…

宇宙学与河外天体物理 · 物理学 2022-07-20 Bruno Villasenor , Brant Robertson , Piero Madau , Evan Schneider

(abridged) We present observations of the high-redshift QSO GB1759+7539 (z=3.05) obtained with HIRES on the Keck 10m telescope. The spectrum has a resolution of FWHM = 7 km/s, and a typical signal-to-noise ratio per 2 km/s pixel of ~25 in…

天体物理学 · 物理学 2009-10-31 P. J. Outram , F. H. Chaffee , R. F. Carswell

We present new measurements of the free-streaming of warm dark matter (WDM) from Lyman-$\alpha$ flux-power spectra. We use data from the medium resolution, intermediate redshift XQ-100 sample observed with the X-shooter spectrograph ($z=3 -…

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…

宇宙学与河外天体物理 · 物理学 2025-07-02 Roger de Belsunce , Mikhail M. Ivanov , James M. Sullivan , Kazuyuki Akitsu , Shi-Fan Chen

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…

天体物理学 · 物理学 2016-08-30 Patrick Petitjean , Jan P. Mücket , Ron Kates

We briefly discuss the relevance of Lyman alpha forest observations for measuring cosmological parameters, comparing the properties of high z QSO spectra with those of artifical spectra from hydrodynamic simulations, based on hierarchical…

天体物理学 · 物理学 2007-05-23 Michael Rauch

The 1D flux power spectrum ($P_{\mathrm{1D}}$) of the Ly$\alpha$ forest provides an exceptionally high-resolution probe of structure formation down to small scales ($k\approx1-10~\text{$h~$Mpc$^{-1}$}$). These scales carry the imprints of…

宇宙学与河外天体物理 · 物理学 2026-04-13 N. G. Karaçaylı , M. Ivanov , R. de Belsunce , C. Ravoux , J. M. Sexton , Z. Lukić

We determine the thermal evolution of the intergalactic medium (IGM) over $3\, \mathrm{Gyr}$ of cosmic time $1.8<z<5.4$ by comparing measurements of the Ly{\alpha} forest power spectrum to a suite of $\sim70$ hydrodynamical simulations. We…

宇宙学与河外天体物理 · 物理学 2019-02-13 Michael Walther , Jose Oñorbe , Joseph F. Hennawi , Zarija Lukić

We aim to construct a machine-learning approach that allows for a pixel-by-pixel reconstruction of the intergalactic medium (IGM) density field for various warm dark matter (WDM) models using the Lyman-alpha forest. With this regression…

We present constraints on the masses of extremely light bosons dubbed fuzzy dark matter from Lyman-$\alpha$ forest data. Extremely light bosons with a De Broglie wavelength of $\sim 1$ kpc have been suggested as dark matter candidates that…

宇宙学与河外天体物理 · 物理学 2017-08-01 Vid Iršič , Matteo Viel , Martin G. Haehnelt , James S. Bolton , George D. Becker

We study the sample variance of the matter power spectrum for the standard Lambda Cold Dark Matter universe. We use a total of 5000 cosmological N-body simulations to study in detail the distribution of best-fit cosmological parameters and…

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-alpha forest and the Cosmic Microwave Background are used to set…

天体物理学 · 物理学 2016-08-30 Ofer Lahav
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