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Based on the disk galaxy formation theory within the framework of standard LCDM hierarchical picture, we selected modelled DLAs, according to their observational criterion, by Monte Carlo simulation with the random inclinations being…

Astrophysics · Physics 2015-06-24 J. L. Hou , C. G. Shu , S. Y. Shen , R. X. Chang , W. P. Chen , C. Q. Fu

We investigate chemical enrichment in Damped Lyman alpha (DLA) systems in the hierarchical structure formation scenario using a semi-analytic model of galaxy formation. The model developed by Nagashima, Totani, Gouda and Yoshii takes into…

Astrophysics · Physics 2009-11-10 Katsuya Okoshi , Masahiro Nagashima , Naoteru Gouda , Satoshi Yoshioka

We estimate the intrinsic neutral gas density in Damped Lyman Alpha systems ($\Omega_{HI}^{(DLA)}$) in the redshift range $ 2.2 \lesssim z \lesssim 5$ from the DLA SDSS DR_3 sample of optically selected quasars. We take into account…

Astrophysics · Physics 2008-11-26 M. Trenti , M. Stiavelli

We use spectroscopy of close pairs of quasars to study diffuse gas in the circumgalactic medium (CGM) surrounding a sample of 40 Damped Lya systems (DLAs). The primary sightline in each quasar pair probes an intervening DLA in the redshift…

Astrophysics of Galaxies · Physics 2015-08-06 Kate H. R. Rubin , Joseph F. Hennawi , J. Xavier Prochaska , Robert A. Simcoe , Adam Myers , Marie Wingyee Lau

We present a detailed analysis of a very unusual sub-damped Lyman alpha (sub-DLA) system at redshift z=2.304 towards the quasar Q0453-423, based on high signal-to-noise (S/N), high-resolution spectral data obtained with VLT/UVES. With a…

Astrophysics of Galaxies · Physics 2016-03-23 Anne Fox , Philipp Richter

Neutral hydrogen traces gravitational potentials. In the nearby universe, 21cm emission-line surveys show that the bulk of the HI resides in well-formed, optically-luminous galaxies. At high redshift, 21cm line absorption against background…

Astrophysics · Physics 2007-05-23 F. H. Briggs

We present a sample of local analogs for high-redshift galaxies selected in the Sloan Digital Sky Survey (SDSS). The physical conditions of the interstellar medium (ISM) in these local analogs resemble those in high-redshift galaxies. These…

Astrophysics of Galaxies · Physics 2016-05-25 Fuyan Bian , Lisa Kewley , Michael Dopita , Stephanie Juneau

We present a comparison between the observed properties of damped Lyman alpha systems (DLAs) and the predictions of simple models for the evolution of present day disk galaxies, including both low and high surface brightness galaxies. We…

Astrophysics · Physics 2008-11-26 Samuel Boissier , Celine Peroux , Max Pettini

Quasar damped Ly-alpha (DLA) absorption line systems with redshifts z<1.65 are used to trace neutral gas over approximately 70 per cent of the most recent history of the Universe. However, such systems fall in the UV and are rarely found in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 David A. Turnshek , Eric M. Monier , Sandhya M. Rao , Timothy S. Hamilton , Gendith M. Sardane , Ryan Held

We report ALMA observations of the neutral atomic carbon transitions [CI] and multiple CO lines in a sample of $\sim30$ main sequence galaxies at $z\sim1$, including novel information on [CI](2-1) and CO(7-6) for 7 of such normal objects.…

Images of five QSO fields containing six damped Lyman alpha (DLA) systems at redshifts 0.09<z<0.53 are presented. Identifications for the DLA galaxies giving rise to the DLA systems are made. The observed and modeled characteristics of the…

The HI 21cm absorption optical depth and the N(HI) derived from Lya absorption can be combined to yield the spin temperature (Ts) of DLAs. Although Ts measurements exist for samples of DLAs with z <0.6 and z >1.7, the intermediate redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Sara L. Ellison , Nissim Kanekar , J. Xavier Prochaska , Emmanuel Momjian , Gabor Worseck

Details of processes through which galaxies convert their gas into stars need to be studied in order to obtain a complete picture of galaxy formation. One way to tackle these phenomena is to relate the HI gas and the stars in galaxies.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Celine Peroux , Nicolas Bouche , Varsha P. Kulkarni , Donald G. York , Giovanni Vladilo

We present the first Keck/OSIRIS infrared IFU observations of a high redshift damped Lyman-alpha (DLA) galaxy detected in the line of sight to a background quasar. By utilizing the Laser Guide Star Adaptive Optics (LGSAO) to reduce the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Regina A. Jorgenson , Arthur M. Wolfe

We present results from a search for galaxies that give rise to damped Lyman alpha (DLA), subDLA, and Lyman limit system (LLS) absorption at redshifts 0.1 ~< z ~< 1 in the spectra of background quasars. The sample was formed from a larger…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Sandhya M. Rao , Michele Belfort-Mihalyi , David A. Turnshek , Eric M. Monier , Daniel B. Nestor , Anna M. Quider

We present a systematic study of deuterated molecular hydrogen (HD) at high redshift, detected in absorption in the spectra of quasars. We present four new identifications of HD lines associated with known $\rm H_2$-bearing Damped…

Astrophysics of Galaxies · Physics 2021-06-30 D. N. Kosenko , S. A. Balashev , P. Noterdaeme , J. -K. Krogager , R. Srianand , C. Ledoux

We report {\it HST} COS spectroscopy of 10 quasars with foreground star-forming galaxies at 0.02$<$$z$$<$ 0.14 within impact parameters of $\sim$1-7 kpc. We detect damped/sub-damped Ly$\alpha$ absorption in 100$\%$ of cases where no…

The properties of galaxies at redshift $z>6$ hold the key to our understanding of the early stages of galaxy evolution and can potentially identify the sources of the ultraviolet radiation that give rise to the epoch of reionisation. The…

We derive the distribution of neutral and ionized gas in high redshift clouds which are optically thick to hydrogen ionizing radiation, using published data on Lyman-limit and Damped Lyman-alpha absorption systems in the redshift range 1.75…

Astrophysics · Physics 2009-10-31 Edvige Corbelli , Edwin E. Salpeter , Rino Bandiera

We present a sample of 33 damped Lyman alpha systems (DLAs) discovered in the Sloan Digital Sky Survey (SDSS) whose absorption redshifts (z_abs) are within 6000 km/s of the QSO's systemic redshift (z_sys). Our sample is based on 731 2.5 <…

Astrophysics · Physics 2009-11-13 David M. Russell , Sara L. Ellison , Chris R. Benn
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