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Related papers: On the (Non)Evolution of HI Disks over Cosmic Time

200 papers

We present new empirical constraints on the evolution of $\rho_{\rm H_2}$, the cosmological mass density of molecular hydrogen, back to $z\approx2.5$. We employ a statistical approach measuring the average observed $850\mu{\rm m}$ flux…

The history and progress of DLA research over the past several decades is reviewed here. Larger datasets and deeper surveys, particularly over the last couple of years, have improved our knowledge of the neutral gas content and distribution…

Astrophysics · Physics 2009-11-11 Sandhya M. Rao

HI-Selected galaxies obey a linear relationship between their maximum detected radius Rmax and rotational velocity. This result covers measurements in the optical, ultraviolet, and HI emission in galaxies spanning a factor of 30 in size and…

Astrophysics of Galaxies · Physics 2018-03-23 Gerhardt R. Meurer , Danail Obreschkow , O. Ivy Wong , Zheng Zheng , Fiona M. Audcent-Ross , D. J. Hanish

We derive the statistical properties of neutral gas at redshifts 0.11<z<1.65 from UV measurements of quasar Lyman alpha absorption lines corresponding to 369 MgII systems with $W^{\lambda2796}_{0} \ge 0.3$ \AA. In addition to the 41 damped…

Astrophysics of Galaxies · Physics 2017-08-23 Sandhya M. Rao , David A. Turnshek , Gendith M. Sardane , Eric M. Monier

We present full modeling of tangent point emission of HI as seen in the 21 cm transition in the inner Galaxy ($R \simeq 3-8 \kpc$). The model used takes into account emission from a large path length along the line of sight, corresponding…

Astrophysics · Physics 2011-03-28 Sangeeta Malhotra

New HI observations are presented for a complete sample of 109 low luminosity star-forming galaxies taken from the KPNO International Spectroscopic Survey (KISS), the first CCD-based wide-field objective-prism survey for emission-line…

We present HST/WFC3 narrowband imaging of the H-alpha emission in a sample of eight gravitationally-lensed galaxies at z = 1 - 1.5. The magnification caused by the foreground clusters enables us to obtain a median source plane spatial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 R. C. Livermore , T. Jones , J. Richard , R. G. Bower , R. S. Ellis , A. M. Swinbank , J. R. Rigby , Ian Smail , H. Ebeling , R. A. Crain

Using IRAM 30m, SEST 15m, and Nancay radiotelescopes, we have gathered the 1mm continuum emission, spectra of the J=1--0 CO line and of the HI line at 21cm for two samples of IRAS galaxies. Using these data, we have estimated the HI masses,…

Astrophysics · Physics 2016-08-30 Paola Andreani , Fabienne Casoli , Maryvonne Gerin

(Abridged) Several aspects of the evolution of star-forming galaxies are studied using measures of the 2-dimensional surface brightness profile of a sample of 341 faint objects selected from the CFRS and LDSS redshift surveys that have been…

In this paper we present an attempt to estimate the redshift evolution of the molecular to neutral gas mass ratio within galaxies (at fixed stellar mass). For a sample of five nearby grand design spirals located on the Main Sequence (MS) of…

Astrophysics of Galaxies · Physics 2021-01-27 Laura Morselli , Alvio Renzini , Andrea Enia , Giulia Rodighiero

The abundances of iron and oxygen are homogeneously determined in a sample of 523 nearby (d<150 pc) FGK disk and halo stars with metallicities in the range -1.5<[Fe/H]<0.5. The oxygen abundances were inferred from a restricted non-LTE…

Astrophysics · Physics 2009-11-13 I. Ramirez , C. Allende Prieto , D. L. Lambert

The neutral atomic gas content of individual galaxies at large cosmological distances has until recently been difficult to measure due to the weakness of the hyperfine HI 21-cm transition. Here we estimate the HI gas mass of a sample of…

Aims: We derive the 3-D HI volume density distribution for the Galactic disk out to R = 60 kpc. Methods: Our analysis is based on parameters for the warp and rotation curve derived previously. The data are taken from the…

Astrophysics · Physics 2015-05-13 P. M. W. Kalberla , L. Dedes

We present a new map of interstellar reddening, covering the 39\% of the sky with low {\rm HI} column densities ($N_{\rm HI} < 4\times10^{20}\,\rm cm^{-2}$ or $E(B-V)\approx 45\rm\, mmag$) at $16\overset{'}{.}1$ resolution, based on all-sky…

Astrophysics of Galaxies · Physics 2017-09-06 Daniel Lenz , Brandon S. Hensley , Olivier Doré

Quasar absorbers provide a powerful observational tool with which to probe both galaxies and the intergalactic medium up to high redshift. We present a study of the evolution of the column density distribution, f(N,z), and total neutral…

Astrophysics · Physics 2007-05-23 Celine Peroux , Mike J. Irwin , Richard G. McMahon , Lisa J. Storrie-Lombardi

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 study the evolution of atomic and molecular gas in galaxies in semi-analytic models of galaxy formation that include new modeling of the partitioning of cold gas in galactic discs into atomic, molecular, and ionised phases. We adopt two…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Gergo Popping , Rachel S. Somerville , Scott C. Trager

We use the Hubble Space Telescope (HST) archive of ultraviolet (UV) quasar spectroscopy to conduct the first blind survey for damped Ly-alpha absorbers (DLAs) at low redshift (z < 1.6). Our statistical sample includes 463 quasars with…

We probe the physical conditions in high redshift galaxies, specifically, the Damped Lyman-alpha Systems (DLAs) using neutral carbon (CI) fine structure lines and molecular hydrogen (H2). We report five new detections of CI and analyze the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Regina A. Jorgenson , Arthur M. Wolfe , J. Xavier Prochaska

Using a spectral stacking technique, we measure the neutral hydrogen (HI) properties of a sample of galaxies at $z < 0.11$ across 35 pointings of the Westerbork Synthesis Radio Telescope (WSRT). The radio data contains 1,895 galaxies with…