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Related papers: MODELS OF LYMAN-ALPHA CLOUDS

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A convincing physical picture for the Lyman-alpha forest has emerged from simulations and related semi-analytic studies of structure formation models. Observations can be be used in the context of this picture to study cosmology using the…

Astrophysics · Physics 2007-05-23 Rupert Croft , David Weinberg , Neal Katz , Lars Hernquist

Estimates of Omega_baryon from primordial nucleosynthesis together with standard assumptions about the ionization state of low column density Lyman alpha forest clouds can be used to determine an upper limit for the cloud thickness along…

Astrophysics · Physics 2016-06-08 Michael Rauch , Martin G. Haehnelt

We investigate the metal contents of Lyman-alpha clouds at 2.2<z<3.6 with 10^13.5<N(HI)<10^14 cm-2 using high resolution, high S/N spectra of 9 quasars obtained with the 10m Keck I telescope. Using an composite spectrum analysis technique,…

Astrophysics · Physics 2007-05-23 Limin Lu , Wallace L. W. Sargent , Thomas A. Barlow , Michael Rauch

While the concept of "clustering" primarily refers to galaxies, the fact is that galaxies can be neglected - at least in terms of mass - when considering the continuous competition between accretion and relaxation processes of dark matter…

Astrophysics · Physics 2007-05-23 M. Pierre

We investigate a model for the high-ionization state gas associated with observed damped Lyman-alpha systems, based on a semi-analytic model of galaxy formation set within the paradigm of hierarchical structure formation. In our model, the…

Astrophysics · Physics 2009-11-07 Ariyeh H. Maller , Jason X. Prochaska , Rachel S. Somerville , Joel R. Primack

We present moderate resolution data for 39 QSOs at z $\approx$ 2 obtained at the Multiple Mirror Telescope. These data are combined with spectra of comparable resolution of 60 QSOs with redshifts greater than 1.7 found in the literature to…

Astrophysics · Physics 2009-10-31 J. Scott , J. Bechtold , A. Dobrzycki

The brightnesses of supernovae are commonly understood to indicate that cosmological expansion is accelerating due to dark energy. However the entire discussion presumes a perfectly transparent universe because no effects of reddening…

Astrophysics · Physics 2015-06-24 Rudolph E. Schild , Marius Dekker

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

This article concerns the formation and structure of dark matter halos, including (1) their radial density profiles, (2) their abundance, and (3) their merger rates. The last topic may be relevant to the nature of the small, bright,…

Astrophysics · Physics 2007-05-23 J. R. Primack , J. S. Bullock , A. A. Klypin , A. V. Kravtsov

We explore molecular cloud properties and the physics of CO transition lines in z >~ 6 Lyman-break galaxies and predict their CO fluxes using an analytic formalism built from global models of star formation in high-redshift galaxies that…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-09 Joseph A. Muñoz , Steven R. Furlanetto

This paper describes a study of the Lyman-alpha forest absorption clouds along the quasar sightline Q0000-26 (zem=4.1). The spectrum was obtained with the High Resolution Spectrometer on the 10m Keck telescope. We derive accurate H I column…

Astrophysics · Physics 2009-10-28 Limin Lu , Wallace L. W. Sargent , Donna S. Womble , Masahide Takada-Hidai

Cosmological simulations with gas provide a detailed description of the intergalactic medium, making possible predictions of neutral hydrogen absorption in the spectra of background QSOs. We present results from a high-resolution…

Astrophysics · Physics 2009-10-28 Lars Hernquist , Neal Katz , David H. Weinberg , Jordi Miralda-Escude

The isotropy of the Lyman-alpha forest in real-space uniquely provides a measurement of cosmic geometry at z > 2. The angular diameter distance for which the correlation function along the line of sight and in the transverse direction agree…

The low-redshift Ly-alpha forest of absorption lines provides a probe of large-scale baryonic structures in the intergalactic medium, some of which may be remnants of physical conditions set up during the epoch of galaxy formation. We…

Astrophysics · Physics 2019-08-17 J. Michael Shull , Steven V. Penton , John T. Stocke

A novel mechanism of the formation of compact dusty clouds in astrophysical environments is discussed. It is shown that the balance of collective forces operating in space dusty plasmas can result in the effect of dust self-confinement,…

Astrophysics of Galaxies · Physics 2015-06-17 V. N. Tsytovich , A. V. Ivlev , A. Burkert , G. E. Morfill

For the purpose of studying the properties of heavy-elements associated with the Lyman-$\alpha$\ forest, we observed the gravitational lens Q1422+2309. We used the HIRES instrument on the W.M. Keck telescope to obtain a high-resolution,…

Astrophysics · Physics 2016-01-27 D. S. Womble , W. L. W. Sargent , R. S. Lyons

We use new observations of very weak CIV absorption lines associated with high-redshift Lyman-alpha absorption systems to measure the high-redshift Lyman-alpha line two-point correlation function (TPCF). These very weak CIV absorption lines…

Astrophysics · Physics 2009-10-28 A. Fernandez-Soto , K. M. Lanzetta , X. Barcons , R. F. Carswell , J. K. Webb , A. Yahil

Observations of damped Lyman alpha systems offer a unique window on the neutral-gas reservoirs that gave rise to galaxies at high redshifts. This review focuses on critical properties such as the H I and metal content of the gas and on…

Astrophysics · Physics 2009-07-09 Arthur M. Wolfe , Eric Gawiser , Jason X. Prochaska

Recent observations have discovered long (up to ~110 Mpc/h), opaque Gunn-Peterson troughs in the z ~ 5.5 Lyman-alpha forest, which are challenging to explain with conventional models of the post-reionization intergalactic medium. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-11 Frederick B. Davies , George D. Becker , Steven R. Furlanetto
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