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相关论文: Statistical selection of high-redshift, neutral-hy…

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We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15-0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope.…

We investigate the gravitational lensing properties of lines of sight containing multiple cluster-scale halos, motivated by their ability to lens very high-redshift (z ~ 10) sources into detectability. We control for the total mass along…

宇宙学与河外天体物理 · 物理学 2015-06-04 Kenneth C. Wong , S. Mark Ammons , Charles R. Keeton , Ann I. Zabludoff

We present adaptive optics-assisted integral field spectroscopy around the Ha or Hb lines of 12 gravitationally lensed galaxies obtained with VLT/SINFONI, Keck/OSIRIS and Gemini/NIFS. We combine these data with previous observations and…

Observations of anisotropies in the brightness temperature of the 21 cm line of neutral hydrogen from the period before reionization would shed light on the dawn of the first stars and galaxies. In this paper, we use large-scale…

宇宙学与河外天体物理 · 物理学 2011-02-16 M. G. Santos , M. B. Silva , J. R. Pritchard , R. Cen , A. Cooray

We have placed limits on the cosmological significance of gas-rich low surface-brightness (LSB) galaxies as a proportion of the total population of gas-rich galaxies by carrying out a very deep survey (HIDEEP) for neutral hydrogen (HI) with…

Whereas considerable effort has been afforded in understanding the properties of galaxies, a full physical picture, connecting their baryonic and dark-matter content, super-massive black holes, and (metric) theories of gravity, is still…

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…

宇宙学与河外天体物理 · 物理学 2017-03-22 Bharat Kumar Gehlot , Jasjeet Singh Bagla

We introduce a new method for constraining the redshift distribution of a set of galaxies, using weak gravitational lensing shear. Instead of using observed shears and redshifts to constrain cosmological parameters, we ask how well the…

宇宙学与河外天体物理 · 物理学 2015-06-11 D. Wittman , W. A. Dawson

We use a dense redshift survey in the foreground of the Subaru GTO2deg^2 weak lensing field (centered at $\alpha_{2000}$ = 16$^h04^m44^s$;$\delta_{2000}$ =43^\circ11^{\prime}24^{\prime\prime}$) to assess the completeness and comment on the…

宇宙学与河外天体物理 · 物理学 2015-05-27 Michael J. Kurtz , Margaret J. Geller , Yousuke Utsumi , Satoshi Miyazaki , Ian P. Dell'Antonio , Daniel G. Fabricant

We present a novel approach to extracting dwarf galaxies from photometric data to measure their average halo mass profile with weak lensing. We characterise their stellar mass and redshift distributions with a spectroscopic calibration…

The substantial decrease in star formation density from z=1 to the present day is curious given the relatively constant neutral gas density over the same epoch. Future radio astronomy facilities, including the SKA and pathfinder telescopes,…

星系天体物理 · 物理学 2016-07-27 Natasha Maddox , Matt J. Jarvis , Tom Oosterloo

We present the largest homogeneous survey of $z>4.4$ damped Lyman-$\alpha$ systems (DLAs) using the spectra of 163 QSOs that comprise the Giant Gemini GMOS (GGG) survey. With this survey we make the most precise high-redshift measurement of…

We perform a deep search for galaxies in the redshift range 6.5<z<7.5, to measure the evolution of the number density of luminous galaxies in this redshift range and derive useful constraints on the evolution of their Luminosity Function.…

We report on a novel search for radio gravitational lenses. Using the Very Large Array, we imaged ten candidates with both dual redshifts in Sloan Digital Sky Survey spectra and 1.4 GHz radio flux >2 mJy in the FIRST survey. The VLA maps…

天体物理学 · 物理学 2010-11-11 Edward R. Boyce , Judd D. Bowman , Adam S. Bolton , Jacqueline N. Hewitt , Scott Burles

We present a catalog of 49 spectroscopic strong gravitational lens candidates selected from a Sloan Digital Sky Survey sample of 50996 luminous red galaxies. Potentially lensed star-forming galaxies are detected through the presence of…

天体物理学 · 物理学 2009-11-10 Adam S. Bolton , Scott Burles , David J. Schlegel , Daniel J. Eisenstein , J. Brinkmann

We detect the weak gravitational lensing distortion of 450,000 background galaxies (20<R<23) by 790 foreground galaxies (R<18) selected from the Las Campanas Redshift Survey (LCRS). This is the first detection of weak lensing by field…

天体物理学 · 物理学 2009-10-31 D. R. Smith , G. M. Bernstein , P. Fischer , R. M. Jarvis

Understanding properties of the first sources in the Universe using the redshifted \HI ~21-cm signal is one of the major aims of present and upcoming low-frequency experiments. We investigate the possibility of imaging the redshifted 21-cm…

宇宙学与河外天体物理 · 物理学 2016-11-15 Raghunath Ghara , T. Roy Choudhury , Kanan K. Datta , Samir Choudhuri

We obtained deep 8.5'x8.5' near-infrared images within four high-redshift survey fields, measured the Ks magnitudes of 300 optically selected galaxies with spectroscopic redshift 1.8<z<2.6, and compared the spatial clustering strength of…

We present a list of 13 candidate gravitationally lensed submillimeter galaxies (SMGs) from 95 square degrees of the Herschel Multi-tiered Extragalactic Survey, a surface density of 0.14\pm0.04deg^{-2}. The selected sources have 500um flux…