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Related papers: Radiation Pressure in Lyman-alpha Forest Clouds

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We introduce a new set of large scale, high resolution hydrodynamical simulations of the intergalactic medium: the Sherwood simulation suite. These are performed in volumes 10^3-160^3 h^-3 comoving Mpc^{3}, span almost four orders of…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-07 James S. Bolton , Ewald Puchwein , Debora Sijacki , Martin G. Haehnelt , Tae-Sun Kim , Avery Meiksin , John A. Regan , Matteo Viel

We present a novel technique for calculating the two-point autocorrelation function of the Lyman-alpha forest based on the relation between the two-point correlation function and the Neighbor Probability Distribution Functions. The…

Astrophysics · Physics 2009-10-28 Avery Meiksin , Francois R. Bouchet

We present the far-UV spectrum of the quasar HS1700+6416 taken with FUSE. This QSO provides the second line of sight with the HeII absorption resolved into a Ly alpha forest structure. Since HS1700+6416 is slightly less redshifted (z=2.72)…

The Lyman-$\alpha$ forest is a valuable probe of dark matter models featuring a scale-dependent suppression of the power spectrum as compared to $\Lambda$CDM. In this work, we present a new estimator of the Lyman-$\alpha$ flux power…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Mathias Garny , Thomas Konstandin , Laura Sagunski , Sean Tulin

Absorption of the Lyman-$\alpha$ radiation on Interstellar Neutral Hydrogen (ISN H) atoms in the heliosphere is a potentially important effect to account for in precise gas distribution simulations. In this paper we develop a method to…

Solar and Stellar Astrophysics · Physics 2022-03-07 Izabela Kowalska-Leszczynska , Marzena A. Kubiak , Maciej Bzowski

The Ly$\alpha$ emission line is one of the main observables of galaxies at high redshift, but its output depends strongly on the neutral gas distribution and kinematics around the star-forming regions where UV photons are produced. We…

Fluctuations in Lyman-$\alpha$ (Ly$\alpha$) forest transmission towards high-$z$ quasars are partially sourced from spatial fluctuations in the ultraviolet background (UVB), the level of which are set by the mean free path of ionizing…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-10 Molly Wolfson , Joseph F. Hennawi , Frederick B. Davies , Jose Oñorbe

Lyman-$\alpha$(Ly$\alpha$) forest in the spectra of distant quasars encodes the information of the underlying cosmic density field at smallest scales. The modelling of the upcoming large and high-fidelity forest data using cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-10 Bhaskar Arya

The thermal state of the intergalactic medium (IGM) at z < 6 constrains the nature and timing of cosmic reionization events, but its inference from the Ly-alpha forest is degenerate with the 3-D structure of the IGM on ~100 kpc scales,…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Girish Kulkarni , Joseph F. Hennawi , Jose Oñorbe , Alberto Rorai , Volker Springel

We combine a cosmological reionization simulation with box size of 100Mpc/h on a side and a Monte Carlo Lyman-alpha (Lya) radiative transfer code to model Lyman Alpha Emitters (LAEs) at z~5.7. The model introduces Lya radiative transfer as…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Zheng Zheng , Renyue Cen , Hy Trac , Jordi Miralda-Escude

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

We measure the power spectrum, P_F(k,z), of the transmitted flux in the Ly-alpha forest using 3035 high redshift quasar spectra from the Sloan Digital Sky Survey. This sample is almost two orders of magnitude larger than any previously…

We analyze the flux power spectrum and its covariance using simulated Lyman alpha forests. We find that pseudo-hydro techniques are good approximations of hydrodynamical simulations at high redshift. However, the pseudo-hydro techniques…

Astrophysics · Physics 2009-11-11 Hu Zhan , Romeel Dave , Daniel Eisenstein , Neal Katz

Extended Lyman-alpha emission is now commonly detected around high redshift galaxies through stacking and even on individual basis. Despite recent observational advances, the physical origin of these Lyman-alpha halos (LAHs), as well as…

Molecular hydrogen absorption in the damped Lyman-alpha system at z = 2.34 towards quasar Q1232+082 is analyzed in order to derive a constraint on a possible temporal variation of the proton-to-electron mass ratio, mu, over cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 M. Daprà , M. van der Laan , M. T. Murphy , W. Ubachs

We compare the low redshift (z ~ 0.1) Lyman-alpha forest from hydrodynamical simulations with data from the Cosmic Origin Spectrograph (COS). We find tension between the observed number of lines with b-parameters in the range 25-45 km/s and…

Astrophysics of Galaxies · Physics 2017-04-19 M. Viel , M. G. Haehnelt , J. S. Bolton , T. -S. Kim , E. Puchwein , F. Nasir , B. P. Wakker

We examine the impact of gas pressure on the transverse coherence of high-redshift (2 <= z <= 4) Lyman-alpha forest absorption along neighboring lines of sight that probe the gas Jeans scale (projected separation Delta r <= 500 kpc/h…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-12 Molly S. Peeples , David H. Weinberg , Romeel Davé , Mark A. Fardal , Neal Katz

Various recent studies proved that cosmological models with a significant contribution from cold dark matter isocurvature perturbations are still compatible with most recent data on cosmic microwave background anisotropies and on the shape…

Astrophysics · Physics 2009-11-13 Maria Beltran , Juan Garcia-Bellido , Julien Lesgourgues , Matteo Viel

We use high quality echelle spectra of 24 QSOs to provide a calibrated measurement of the total amount of Lyman-alpha forest absorption (DA) over the redshift range 2.2 < z < 3.2. Our measurement of DA excludes absorption from metal lines…

We present new measurements of the flux power-spectrum P(k) of the $z<0.5$ HI Lyman-$\alpha$ forest spanning scales k ~ 0.001-0.1 s/km. These results were derived from 65 far ultraviolet quasar spectra (resolution R~18000) observed with the…

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