English
Related papers

Related papers: Improved constraints on the cosmological parameter…

200 papers

Published data from long-term observations of a strip of sky at declination +5 degrees carried out at 7.6 cm on the RATAN-600 radio telescope are used to estimate some statistical properties of radio sources. Limits on the sensitivity of…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-24 Yu. N. Parijskij , N. S. Soboleva , A. V. Temirova , N. N. Bursov , O. P. Zhelenkova

Observational evidence for the accelerated expansion of the universe requires dark energy for its explanation if general relativity is an accurate model of gravity. However, dark energy is a mysterious quantity and we do not know much about…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-14 Narayan Khadka

Global VLBI observations at 5 GHz have been performed to study the source morphology in 10 compact steep-spectrum (CSS) sources selected from the Peacock & Wall catalogue with the aim of finding asymmetric structures produced by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 D. Dallacasa , M. Orienti , C. Fanti , R. Fanti , C. Stanghellini

We present the optical and infrared identifications of the 266 radio sources detected at 20 cm with the Very Large Array in the Chandra Deep Field South (Kellermann et al. 2008). Using deep i-band Advanced Camera for Surveys, R-band Wide…

A VLA Sky Survey of the extragalactic sky at S band (2-4 GHz) with polarization information can uniquely probe the magneto-ionic medium in a wide range of astrophysical environments over cosmic time. For a shallow all-sky survey, we expect…

We report on first results of an ongoing effort to image a small sample of high-redshift radio galaxies (HzRGs) with milliarcsecond (mas) resolution, using very-long-baseline interferometry (VLBI) techniques. Here, we present 1.7 and 5.0…

Astrophysics · Physics 2009-11-11 Miguel A. Perez-Torres , Carlos De Breuck , Wil van Breugel , George Miley

We present new sub-arcsecond-resolution Karl G. Jansky Very Large Array (VLA) imaging at 10 GHz of 155 ultra-luminous ($L_{\rm bol}\sim10^{11.7-14.2} L_\odot$) and heavily obscured quasars with redshifts $z \sim0.4-3$. The sample was…

We present a data-driven technique to analyze multifrequency images from upcoming cosmological surveys mapping large sky area. Using full information from the data at the two-point level, our method can simultaneously constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 Yun-Ting Cheng , Benjamin D. Wandelt , Tzu-Ching Chang , Olivier Dore

We analyze optical and radio properties of radiogalaxies detected in the Sloan Digital Sky Survey (SDSS). The sample of radio sources are selected from the catalogue of Kimball & Ivezi\'c (2008) with flux densities at 325, 1400 and 4850…

Astrophysics of Galaxies · Physics 2015-05-18 Carlos G. Bornancini , Ana Laura O'Mill , Sebastian Gurovich , Diego Garcia Lambas

We present the results from the optical component of a survey for damped Lyman-alpha systems (DLAs) towards radio-loud quasars. Our quasar sample is drawn from the Texas radio survey with the following primary selection criteria: z_em >…

Astrophysics · Physics 2009-11-13 Sara L. Ellison , Brian A. York , Max Pettini , Nissim Kanekar

We performed an automated comparison of the FIRST radio survey with the APM optical catalog to find radio lobes with optical counterparts. Based on an initial survey covering ~3000 square degrees, we selected a sample of 33 lens candidates…

Astrophysics · Physics 2009-10-31 J. Lehar , A. Buchalter , R. G. McMahon , C. S. Kochanek , T. W. B. Muxlow

We present the results of a search for damped Lyman-alpha (DLA) systems in the Sloan Digital Sky Survey II (SDSS), Data Release 7. We use a fully automatic procedure to identify DLAs and derive their column densities. The procedure is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 P. Noterdaeme , P. Petitjean , C. Ledoux , R. Srianand

We review the statistical properties of the main populations of radio sources, as emerging from radio and millimeter sky surveys. Recent determinations of local luminosity functions are presented and compared with earlier estimates still in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Gianfranco De Zotti , Marcella Massardi , Mattia Negrello , Jasper Wall

Much evidence has been presented in favor of and against the existence of two distinct populations of quasars, radio-loud and radio-quiet. The SDSS differs from earlier optically selected quasar surveys in the large number of quasars and…

Astrophysics · Physics 2007-05-23 S. Jester , R. Kron

In our previous analysis we investigated the large-scale environment of two samples of radio galaxies (RGs) in the local Universe (i.e. with redshifts z<0.15), classified as FR I and FR II on the basis of their radio morphology. The…

High Energy Astrophysical Phenomena · Physics 2020-04-16 F. Massaro , A. Capetti , A. Paggi , R. D. Baldi , A. Tramacere , I. Pillitteri , R. Campana , A. Jimenez-Gallardo , V. Missaglia

The relationship between the clustering of dark matter and that of luminous matter is often described using the bias parameter. Here, we provide a new method to probe the bias of intermediate to high-redshift radio continuum sources for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Sean Passmoor , Catherine Cress , Andreas Faltenbacher , Russell Johnston , Mathew Smith , Ando Ratsimbazafy , Ben Hoyle

The coherent image distortions induced by weak gravitational lensing can be used to measure the power spectrum of density inhomogeneities in the universe. We present our on-going effort to detect this effect with the FIRST radio survey,…

We present 190 galaxy cluster candidates (most at high redshift) based on galaxy overdensity measurements in the \spitzer/IRAC imaging of the fields surrounding 646 bent, double-lobed radio sources drawn from the Clusters Occupied by Bent…

Astrophysics of Galaxies · Physics 2017-08-02 R. Paterno-Mahler , E. L. Blanton , M. Brodwin , M. L. N. Ashby , E. Golden-Marx , B. Decker , J. D. Wing , G. Anand

We have compiled a sample of 234 ultra-steep-spectrum (USS) selected radio sources in order to find high-redshift radio galaxies. The sample covers the declination range -40deg < DEC < -30deg in the overlap region between the 1400-MHz NRAO…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 J. J. Bryant , J. W. Broderick , H. M. Johnston , R. W. Hunstead , B. M. Gaensler , C. De Breuck

VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum…

Astrophysics · Physics 2007-05-23 Peter D. Barthel , Marianne Vestergaard , Colin J. Lonsdale