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Related papers: A Pilot for a VLA HI Deep Field

200 papers

(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

Distribution of cold gas in the post-reionization era provides an important link between distribution of galaxies and the process of star formation. Redshifted 21 cm radiation from the Hyperfine transition of neutral Hydrogen allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Bharat Kumar Gehlot , Jasjeet Singh Bagla

At present neutral atomic hydrogen (HI) gas in galaxies at redshifts above $z \sim 0.3$ (the extent of 21-cm emission surveys in individual galaxies) and below $z \sim 1.7$ (where the Lyman-$\alpha$ line is not observable with ground-based…

Radio Astronomy is undergoing a renaissance, as the next-generation of instruments provides a massive leap forward in collecting area and therefore raw sensitivity. However, to achieve this theoretical level of sensitivity in the science…

We present results from the largest contiguous narrow-band survey in the near-infrared. We have used WIRCam/CFHT and the lowOH2 filter (1.187$\pm$0.005 $\mu$m) to survey ~10 deg$^2$ of contiguous extragalactic sky in the SA22 field. A total…

We introduce a new Bayesian HI spectral line fitting technique capable of obtaining spectroscopic redshifts for millions of galaxies in radio surveys with the Square Kilometere Array (SKA). This technique is especially well-suited to the…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-28 Ian Harrison , Michelle Lochner , Michael L. Brown

A survey of 329 nearby galaxies (redshift z < 0.045) has been conducted to study the distribution of mass and light within spiral galaxies over a range of environments. The 18 observed clusters and groups span a range of richness, density,…

Astrophysics · Physics 2009-11-10 Nicole P. Vogt , Martha P. Haynes , Terry Herter , Riccardo Giovanelli

The introduction of low-frequency radio arrays over the coming decade is expected to revolutionize the study of the reionization epoch. Observation of the contrast in redshifted 21cm emission between a large HII region and the surrounding…

Astrophysics · Physics 2009-11-11 Stuart Wyithe , Abraham Loeb , David Barnes

The aim of the VIRMOS VLT Deep Survey (VVDS) is to study of the evolution of galaxies, large scale structures and AGNs from a sample of more than 150,000 galaxies with measured redshifts in the range 0<z<5+. The VVDS will rely on the VIMOS…

The Square Kilometre Array (SKA) will produce spectroscopic surveys of tens to hundreds of millions of HI galaxies, eventually covering 30,000 sq. deg. and reaching out to redshift z~2. The huge volumes probed by the SKA will allow for some…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-25 Stefano Camera , Mario G. Santos , Roy Maartens

The evolution of neutral hydrogen (HI) across redshifts is a powerful probe of cosmology, large scale structure in the universe and the intergalactic medium. Using a data-driven halo model to describe the distribution of HI in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-22 Hamsa Padmanabhan

The Square Kilometre Array (SKA) will conduct the biggest spectroscopic galaxy survey ever, by detecting the 21cm emission line of neutral hydrogen (HI) from around a billion galaxies over 3/4 of the sky, out to a redshift of z~2. This will…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-08 S. Yahya , P. Bull , M. G. Santos , M. Silva , R. Maartens , P. Okouma , B. Bassett

We present 21-cm Spectral Line Observations of Neutral Gas with the VLA (21-SPONGE), a Karl G. Jansky Very Large Array (VLA) large project (~600 hours) for measuring the physical properties of Galactic neutral hydrogen (HI). 21-SPONGE is…

Astrophysics of Galaxies · Physics 2018-10-10 Claire E. Murray , Snezana Stanimirovic , W. M. Goss , Carl Heiles , John M. Dickey , Brian Babler , Chang-Goo Kim

We present the results of HI spectral stacking analysis of Giant Metrewave Radio Telescope (GMRT) observations targeting the COSMOS field. The GMRT data cube contains 474 field galaxies with redshifts known from the zCOSMOS-bright 10k…

Astrophysics of Galaxies · Physics 2016-07-27 Jonghwan Rhee , Philip Lah , Jayaram N. Chengalur , Frank H. Briggs , Matthew Colless

We review the analytical prescriptions in the literature to model the 21-cm (emission line surveys/intensity mapping experiments) and Damped Lyman-Alpha (DLA) observations of neutral hydrogen (HI) in the post-reionization universe. While…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 Hamsa Padmanabhan , T. Roy Choudhury , Alexandre Refregier

We conducted the MeerKAT Vela Supercluster survey, named Vela$-$HI, to bridge the gap between the Vela SARAO MeerKAT Galactic Plane Survey (Vela$-$SMGPS, $-2^{\circ} \leq b \leq 1^{\circ}$), and optical and near-infrared spectroscopic…

We demonstrate that the Discrete Persistent Source Extractor (DisPerSE) can be used with spectroscopic redshifts to define the cosmic web and its distance to galaxies in small area deepfields. Here we analyze the use of DisPerSE to identify…

Astrophysics of Galaxies · Physics 2019-07-11 Nicholas Luber , J. H. van Gorkom , Kelley M. Hess , D. J. Pisano , Ximena Fernandez , Emmanuel Momjian

We present a framework for forecasting cosmological constraints from future neutral hydrogen intensity mapping experiments at low to intermediate redshifts. In the process, we establish a simple way of comparing such surveys with optical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-08 Philip Bull , Pedro G. Ferreira , Prina Patel , Mario G. Santos

We report on neutral hydrogen observations of a ~ 5.5 x 5.5 degree field around the NGC 1566 galaxy group with the multibeam narrow-band system on the 64-m Parkes telescope. We detected thirteen HI sources in the field, including two…