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Related papers: Molecular Hydrogen in Damped Ly-alpha Systems: Spa…

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We have carried out a high-resolution imaging search for the galaxy associated with the damped Lyman-alpha (DLA) absorber at z=1.859 toward the z_{em}=2.48 quasar QSO 1244+3443, using the HST and the NICMOS. Images were obtained in the…

The quasar in the Hubble Deep Field South (HDFS), J2233-606 (z=2.23) has been exhaustively observed by ground based telescopes and by the STIS spectrograph on board the Hubble Space Telescope at low, medium and high resolution in the…

We present the results of a long-slit K-band spectroscopic search with CGS4 on UKIRT for H-alpha emission from the objects responsible for high-redshift (z > 2) damped Ly-alpha absorption systems. The objective was to measure the…

Damped Ly_alpha galaxies provide a sample of young galaxies where chemical abundances can be derived throughout the whole universe with an accuracy comparable to that for the local universe. Despite a large spread in redshift, HI column…

Astrophysics · Physics 2015-06-24 Paolo Molaro

We present the Damped Ly$\alpha$ Toolkit for automated detection and characterization of Damped Ly$\alpha$ absorbers (DLA) in quasar spectra. Our method uses quasar spectral templates with and without absorption from intervening DLAs to…

We present HST WFPC2 observations in three bands (F450W, F467M and F814W) of a group of three galaxies at z=2.8 discovered in a ground-based narrow-band search for Lyman alpha emission near the z=2.8 quasar PKS0528-250. One of the galaxies…

Astrophysics · Physics 2009-10-30 Palle Moller , Stephen J. Warren

We use detailed Lyalpha radiative transfer calculations to further test the claim of Rauch et al. (2008) that they have detected spatially extended faint Lyalpha emission from the elusive host population of Damped Lyalpha Absorption systems…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-19 Luke A. Barnes , Martin G. Haehnelt

We report the detection of diffuse Ly$\alpha$ emission, or Ly$\alpha$ halos (LAHs), around star-forming galaxies at $z\approx3.78$ and $2.66$ in the NOAO Deep Wide-Field Survey Bo\"otes field. Our samples consist of a total of $\sim$1400…

Any viable cosmological model must produce enough structure at early epochs to explain the amount of gas associated with high-redshift damped Ly$\alpha$ systems. We study the evolution of damped Ly$\alpha$ systems at redshifts $z\ge 2$ in…

Astrophysics · Physics 2009-10-30 Chung-Pei Ma , Edmund Bertschinger , Lars Hernquist , David H. Weinberg , Neal Katz

We present 4 new measurements of nitrogen abundances and one upper limit in damped Lyman alpha absorbers (DLAs) obtained by means of high resolution (FWHM \~ 7 km/s) UVES/VLT spectra. In addition to these measurements we have compiled data…

Astrophysics · Physics 2011-05-23 M. Centurion , P. Molaro , G. Vladilo , C. Peroux , S. A. Levshakov , V. D'Odorico

In recent decades, significant attention has been dedicated to analytical and observational studies of the atomic hydrogen (HI) to molecular hydrogen (H2) transition in the interstellar medium. We focussed on the Draco diffuse cloud to gain…

Damped Lyman-alpha absorbers (DLAs), seen in absorption against a background quasar, provide the most detailed probes available of element abundances in the Universe over > 90 % of its age. DLAs can be used to observationally measure the…

We present the results of our automatic search for proximate damped Ly$\alpha$ absorption (PDLA) systems in the quasar spectra from the Sloan Digital Sky Survey Data Release 12. We constrain our search to those PDLAs lying within 1500 km…

We investigate the physical properties of molecular hydrogen (H2) in isolated and interacting disk galaxies with different masses and Hubble types by using chemodynamical simulations with H2 formation on dust grains and dust growth and…

Astrophysics of Galaxies · Physics 2017-03-08 Kenji Bekki

Lyman limit and damped Lyman-alpha absorption systems probe the distribution of collapsed, cold gas at high redshift. Numerical simulations that incorporate gravity and gas dynamics can predict the abundance of such absorbers in…

Astrophysics · Physics 2009-10-28 Jeffrey P. Gardner , Neal Katz , Lars Hernquist , David H. Weinberg

The Lyman Alpha damping wing is seen in absorption against the spectra of high-redshift galaxies. Modeling of this wing is a way to measure the volume neutral hydrogen fraction of the Universe, as well as to measure the strength of HI…

Astrophysics of Galaxies · Physics 2025-05-14 Mason Huberty , Claudia Scarlata , Matthew J. Hayes , Simon Gazagnes

The chemical composition of gas in galaxies can be measured in detail from absorption spectroscopy. By studying gas in galaxies in this way, it is possible to investigate the small and faint galaxies, which are the most numerous in the…

Using the Atacama Large Millimeter/sub-millimeter Array, we have detected CO(3-2) line and far-infrared continuum emission from a galaxy associated with a high-metallicity ([M/H] = -0.27) damped Ly-alpha absorber (DLA) at z =2.19289. The…

We combine predictions for several hierarchical cosmogonies with observational evidence on damped Lyman alpha systems to establish a correspondence between the high redshift galaxy population and the properties of damped Lyman alpha…

Astrophysics · Physics 2009-10-31 Martin G. Haehnelt , Matthias Steinmetz , Michael Rauch

We study the effect of local stellar radiation and UVB on the physical properties of DLAs and LLSs at z=3 using cosmological SPH simulations. We post-process our simulations with the ART code for radiative transfer of local stellar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Hidenobu Yajima , Jun-Hwan Choi , Kentaro Nagamine