English
Related papers

Related papers: Improved constraints on the cosmological parameter…

200 papers

In previous attempts to measure Omega_0 from the angular size-redshift (theta-z) relation of double-lobed radio sources, the observed data have been consistent with a static Euclidean universe, rather than with Friedmann models, and past…

Astrophysics · Physics 2009-10-30 Ari Buchalter , David J. Helfand , Robert H. Becker , Richard L. White

A new sample of very large angular size radio sources has been selected from the 1.4 GHz VLA surveys: FIRST and NVSS. This sample will be very useful for an observational constraint on the time evolution of double radio sources, especially…

Astrophysics · Physics 2009-11-06 J. Machalski , M. Jamrozy , S. Zola

The FIRST survey, begun over twenty years ago, provides the definitive high-resolution map of the radio sky. This VLA survey reaches a 20cm detection sensitivity of 1 mJy over 10,575 deg**2 largely coincident with the SDSS area. Images and…

Astrophysics of Galaxies · Physics 2015-06-23 David J. Helfand , Richard L. White , Robert H. Becker

We present a catalog of 246 radio sources found in the central 1 degree of the COSMOS field at 1.4GHz. The VLA pilot project data have a resolution of 1.9"x1.6" and an rms noise limit of ~25-100uJy/beam covering 0.837 sqrdeg. About 20 radio…

We report preliminary results of a visual inspection of ~4300 deg$^2$ covered by 4414 images of the 3-GHz VLA Sky Survey (VLASS, epoch 1.1) in search of extended radio structures. Over 7600 positions were registered, and for a subset of 270…

Astrophysics of Galaxies · Physics 2018-08-23 Agueda C. Villarreal Hernández , Heinz Andernach

A sample of 20 powerful extended radio galaxies with redshifts between zero and two were used to determine constraints on global cosmological parameters. Data for six radio sources were obtained from the VLA archive, analyzed, and combined…

Astrophysics · Physics 2009-10-31 E. J. Guerra , Ruth A. Daly , Lin Wan

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-alpha forest and the Cosmic Microwave Background are used to set…

Astrophysics · Physics 2016-08-30 Ofer Lahav

A sample of 20 powerful extended radio galaxies with redshifts between zero and two were used to determine constraints on global cosmological parameters. Data for six radio sources were obtained from the VLA archive, analyzed, and combined…

Astrophysics · Physics 2015-06-24 Erick J. Guerra , Ruth A. Daly , Lin Wan

In this paper, we explore how the forthcoming generation of large-scale radio continuum surveys, with the inclusion of some degree of redshift information, can constrain cosmological parameters. By cross-matching these radio surveys with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Stefano Camera , Mário G. Santos , David J. Bacon , Matt J. Jarvis , Kim McAlpine , Ray P. Norris , Alvise Raccanelli , Huub Röttgering

The VLA-COSMOS Large Project has imaged the 2 sq.deg. COSMOS field with a resolution of 1.5 arcsec and a sensitivity of about 11 microJy (1 sigma) yielding to a catalog of about 3600 radio sources. In this paper we present a further…

Astrophysics · Physics 2009-11-13 M. Bondi , P. Ciliegi , E. Schinnerer , V. Smolcic , K. Jahnke , C. Carilli , G. Zamorani

We estimate how clustering in large-scale redshift surveys can constrain various cosmological parameters. Depth and sky coverage of modern redshift surveys are greater than ever, opening new possibilities for statistical analysis. We have…

Astrophysics · Physics 2009-11-07 Takahiko Matsubara , Alexander S. Szalay

Measurements of weak gravitational lensing using the cosmic microwave background and the shapes of galaxies have refined our understanding of the late-time history of the Universe. While optical surveys have been the primary source for…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 Alba Kalaja , Ian Harrison , William R Coulton

We have formed a complete sample of 26 low redshift (z < 0.3) giant radio galaxies (GRGs) from the WENSS survey, selected at flux densities above 1 Jy at 325 MHz. We present 10.5-GHz observations with the 100-m Effelsberg telescope of 18…

Our sample of giant radio-source candidates, published in Paper I (Machalski et al. 2001), is updated and supplemented with further radio and optical data. In this paper we present: (i) newly detected host galaxies, their photometric…

Astrophysics · Physics 2009-11-11 J. Machalski , M. Jamrozy , S. Zola , D. Koziel

We have combined a sample of 44984 quasars, selected from the Sloan Digital Sky Survey (SDSS) Data Release 3, with the FIRST radio survey. Using a novel technique where the optical quasar position is matched to the complete radio…

Astrophysics · Physics 2009-11-11 W. H. de Vries , R. H. Becker , R. L. White

We combine the LOw-Frequency ARray (LOFAR) Two-metre Sky Survey (LoTSS) second data release (DR2) catalogue with gravitational lensing maps from the Cosmic Microwave Background (CMB) to place constraints on the bias evolution of LoTSS radio…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 S. J. Nakoneczny , D. Alonso , M. Bilicki , D. J. Schwarz , C. L. Hale , A. Pollo , C. Heneka , P. Tiwari , J. Zheng , M. Brüggen , M. J. Jarvis , T. W. Shimwell

The Combined NVSS-FIRST Galaxy (CoNFIG) survey was defined by selecting all sources with S_1.4GHz > 1.3Jy from the NRAO VLA Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We carried…

Astrophysics · Physics 2009-04-14 Melanie A. Gendre , Jasper V. Wall

We present a quantitative analysis of the astrophysical and cosmological information that can be extracted from the many important wide-area, shallow surveys that will be carried out in the next few years. Our calculations combine the…

Physical sizes of extended radio galaxies can be employed as a cosmological "standard ruler", using a previously developed method. Eleven new radio galaxies are added to our previous sample of nineteen sources, forming a sample of thirty…

Astrophysics · Physics 2009-02-02 Ruth A. Daly , Matthew P. Mory , C. P. O'Dea , P. Kharb , S. Baum , E. J. Guerra , S. G. Djorgovski

We use three samples (3CRR, 6CE and 6C*) selected at low radio frequency to constrain the cosmic evolution in the radio luminosity function (RLF) for the `most luminous' steep-spectrum radio sources. Although intrinsically rare, such…

‹ Prev 1 2 3 10 Next ›