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The Lyman-alpha forest in a blazar-heated Universe
cosmology: theory { methods: numerical | intergalactic medium
2011/10/12
It has been realised only recently that TeV emission from blazars can significantly heat the intergalactic medium (IGM) by pair-producing high-energy electrons and positrons, which in turn excite vigo...
High-ion absorption in the proximate damped Lyman-alpha system toward Q0841+129
quasars: absorption lines – galaxies: high-redshift – galaxies: halos – galaxies: ISM
2011/10/8
We present VLT/UVES spectroscopy of the quasar Q0841+129, whose spectrum shows a proximate damped Lyman-alpha (PDLA) absorber at z=2.47621 and a proximate sub-DLA at z=2.50620, both lying close in red...
On the redshift-evolution of the Lyman-alpha escape fraction and the dust content of galaxies
the redshift-evolution the Lyman-alpha escape fraction
2011/1/10
The Ly-alpha emission line has been proven a powerful tool by which to study evolving galaxies at the highest redshifts. However, in order to use Lya as a physical probe of galaxies, it becomes vital ...
The Signatures of Large-scale Temperature Fluctuations in the Lyman-alpha Forest
Large-scale Temperature Fluctuations the Lyman-alpha Forest
2011/1/11
It appears inevitable that reionization processes would have produced large-scale temperature fluctuations in the intergalactic medium. Using toy temperature models and detailed heating histories in c...
Metallicities and dust content of proximate damped Lyman alpha systems in the Sloan Digital Sky Survey
Metallicities dust content proximate damped Lyman alpha systems
2011/1/11
Composite spectra of 85 proximate absorbers (log N(HI)>20 and velocity difference between the absorption and emission redshift, dv<10,000 km/s) in the SDSS are used to investigate the trends of metal ...
The HETDEX Pilot Survey III: The Low Metallicities of High-Redshift Lyman Alpha Galaxies
galaxies evolution
2010/11/9
We present the results of Keck/NIRSPEC spectroscopic observations of three Ly emitting galaxies (LAEs)at z∼ 2.3 discoveredwith the HETDEX pilot survey. We detectH , [O III], and H emission fro...
A Carbon-enhanced Metal-poor Damped Lyman alpha System: Probing Gas from Population III Nucleosynthesis?
galaxies abundances − galaxies evolution − quasars absorption lines quasars: individual J0035− 0918 − stars carbon − stars
2010/11/10
We present high resolution observations of an extremely metal-poor damped Ly system, at zabs = 2.3400972 in the spectrum of the QSO J0035−0918, exhibiting an abundance pattern consistent with mo...
Chemistry of a protoplanetary disk with grain settling and Lyman alpha radiation
astrochemistry circumstellar matter ISM abundances ISM: molecules planetary systems
2010/11/10
We present results from a model of the chemical evolution of protoplanetary disks. In our models we directly calculate the changing propagation and penetration of a high energy radiation field with Ly...
Extended Lyman-Alpha Emission around Star-forming Galaxies
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/5
Lyman-alpha (Lya) photons generated from reprocessed ionizing photons in star-forming galaxies, once escaping from the interstellar medium, can encounter resonant scatterings with neutral hydrogen ato...
Minimally Parametric Power Spectrum Reconstruction from the Lyman-alpha Forest
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/27
Current results from the Lyman alpha forest assume that the primordial power spectrum of density perturbations follows a simple power law form. We present the first analysis of Lyman alpha data to stu...
We present observations of two strongly lensed $z\gtrsim5$ Lyman-$\alpha$ Emitting (LAE) galaxies that were discovered in the Sloan Giant Arcs Survey (SGAS). We identify the two sources as SGAS J09153...