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Related papers: Dynamical History of Ly \alpha clouds

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We present analysis of two- and three-point correlation functions of Ly$\alpha$ forest (at $2\le z\le 2.5$) using X-Shooter spectra of three background quasar triplets probing transverse separations of 0.5-1.6 pMpc. We present statistics…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Soumak Maitra , Raghunathan Srianand , Patrick Petitjean , Hadi Rahmani , Prakash Gaikwad , Tirthankar Roy Choudhury , Christophe Pichon

A significant fraction of the high-redshift galaxies show strong Lyman emission lines. For redshifts z>5, most known galaxies belong to this class. However, so far not much is known about the physical structure and nature of these objects.…

Astrophysics · Physics 2009-11-13 C. Tapken , I. Appenzeller , S. Noll , S. Richling , J. Heidt , E. Meinkoehn , D. Mehlert

(ABRIDGED) Gaseous halos of nine nearby galaxies (with redshifts cz < 6000 km/s) were probed at large galactocentric radii using background quasars observed with HST GHRS and STIS. The projected quasar-galaxy separations range from 55 to…

Astrophysics · Physics 2014-10-13 Stephanie Cote , Rosemary Wyse , Claude Carignan , Ken Freeman , Tom Broadhurst

We present a large sample of Ly-alpha emitting galaxies spectroscopically confirmed at z~4.5, based on IMACS spectroscopic observations of candidate LAEs in the LALA Cetus field. We identify 110 z~4.5 LAEs based on single line detections…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Jun-Xian Wang , Sangeeta Malhotra , James E. Rhoads , Hao-Tong Zhang , Steven L. Finkelstein

(Abridged) We detect the large-scale structure of Lya emission in the Universe at redshifts z=2-3.5 by measuring the cross-correlation of Lya surface brightness with quasars in SDSS/BOSS. We use a million spectra targeting Luminous Red…

Models are presented for the Lyman alpha emission of dusty high-redshift galaxies by combining the Press-Schechter formalism with a treatment of the inhomogeneous dust distribution inside galaxies. It is found that the amount of Lyman alpha…

Astrophysics · Physics 2008-11-26 Zoltan Haiman , Marco Spaans

The Lyman-alpha forest has opened a new redshift regime for cosmological investigation. At z > 2 it provides a unique probe of cosmic geometry and an independent constraint on dark energy that is not subject to standard candle or ruler…

Astrophysics · Physics 2009-11-13 Andrew R. Marble , Kristoffer A. Eriksen , Chris D. Impey , Lei Bai , Lance Miller

We present spatially resolved maps of six individually-detected Lyman alpha haloes (LAHs) as well as a first statistical analysis of the Lyman alpha (Lya) spectral signature in the circum-galactic medium of high-redshift star-forming…

We present observations with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope of nine most metal-deficient compact star-forming galaxies with oxygen abundances 12+log(O/H)=6.97-7.23, redshifts z=0.02811-0.13320, and…

Astrophysics of Galaxies · Physics 2023-11-06 Y. I. Izotov , T. X. Thuan , N. G. Guseva , D. Schaerer , G. Worseck , A. Verhamme

We present Keck/HIRES abundance measurements and metal-line kinematic profiles of the damped Lyman alpha systems (DLAs) towards the quasars Q0933+733 (z_abs=1.479) and Q0948+433 (z_abs=1.233). These two DLAs have among the five highest HI…

Astrophysics · Physics 2009-11-10 Sandhya M. Rao , Jason X. Prochaska , J. Christopher Howk , Arthur M. Wolfe

Recent work has shown that UV-luminous reionization-era galaxies often exhibit strong Lyman-alpha emission despite being situated at redshifts where the IGM is thought to be substantially neutral. It has been argued that this enhanced…

Detailed analysis of the spectral lines from two low redshift damped Lyman alpha absorbers (DLA) confirms that they are a heterogeneous population. Both systems have low metal abundances of approximately 0.05 to 0.1 solar. The abundance…

Astrophysics · Physics 2007-05-23 A. de la Varga , D. Reimers , D. Tytler , T. Barlow , S. Burles

Separating the cosmological redshifted 21-cm signal from foregrounds is a major challenge. We present the cross-correlation of the redshifted 21-cm emission from neutral hydrogen (HI) in the post-reionization era with the Ly-alpha forest as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Tapomoy Guha Sarkar , Somnath Bharadwaj , Tirthankar Roy Choudhury , Kanan Datta

We present high resolution echelle spectra of 7 proximate damped Lyman alpha (PDLA) systems whose relative velocity separation from the background quasar is Delta V < 3000 km/s. Combining our sample with a further 9 PDLAs from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Sara L. Ellison , J. Xavier Prochaska , Joseph Hennawi , Sebastian Lopez , Chris R. Benn , Chris G. Usher , Arthur M. Wolfe , David R. Russell

We report spectroscopic observations with the Multiple Mirror Telescope for 11 damped Lyman-alpha absorbers (DLAs) or strong DLA candidates at 0.1 < z < 1.5, including several absorbers discovered in the Sloan Digital Sky Survey. In…

We present an analysis of the proximity effect in a sample of ten 2 A resolution QSO spectra of the Ly alpha forest at <z> = 2.9. Rather than investigating variations in the number density of individual absorption lines we employ a novel…

Astrophysics · Physics 2009-11-07 J. Liske , G. M. Williger

We studied Lyman-$\alpha$ (Ly$\alpha$) escape in a statistical sample of 43 Green Peas with HST/COS Ly$\alpha$ spectra. Green Peas are nearby star-forming galaxies with strong [OIII]$\lambda$5007 emission lines. Our sample is four times…

The physical processes which make a galaxy a Lyman Alpha Emitter have been extensively studied for the past 25 years. However, the correlations between physical and morphological properties of galaxies and the strength of the Ly$\alpha$…

In order to ascertain the extent of metal enrichment in the Ly alpha forest, we have analysed a very high S/N spectrum of the z = 3.625 QSO Q1422+231. We find that in high column density Ly alpha clouds, the power law column density…

Astrophysics · Physics 2007-05-23 Sara L. Ellison , Antoinette Songaila , Joop Schaye , Max Pettini

This study presents Keck optical and infrared spectroscopy of the rest-frame ultraviolet and optical emission lines in two Lyman alpha emitting galaxies at z>2. These data provide insight on the evolution of fundamental galaxy scaling…

Astrophysics · Physics 2007-05-23 Chip Kobulnicky , David Koo