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This paper presents the first high-resolution and high-sensitivity study of the radio properties of optically selected type~2 quasars. We used the Very Large Array at 8.4 GHz to observe 59 sources drawn from the Sloan Digital Sky Survey…

宇宙学与河外天体物理 · 物理学 2015-05-14 Dharam Vir Lal , Luis C. Ho

According to a generally accepted paradigm, small intrinsic sizes of Compact Steep Spectrum (CSS) radio sources are a direct consequence of their youth, but in later stages of their evolution they are believed to become large-scale sources.…

天体物理学 · 物理学 2009-11-13 Andrzej Marecki , Magdalena Kunert-Bajraszewska , Ralph E. Spencer

In this data paper we present and characterise the multi-component radio sources identified in the VLA-COSMOS Large Project at 3 GHz (0.75 arcsec resolution, 2.3 {\mu}Jy/beam rms), i.e. the radio sources which are composed of two or more…

More than half of the sources identified by recent radio sky surveys have not been detected by wide-field optical surveys. We present a study based on our co-added image stacking technique, in which our aim is to detect the optical emission…

宇宙学与河外天体物理 · 物理学 2012-09-28 József Varga , István Csabai , László Dobos

The FIRST (Faint Images of the Radio Sky at Twenty Centimeters) survey now covers 1550 square degrees of sky where $07^{h}16 < \alpha < 17^{h}40$ and $28^{\circ}.3 < \delta < 42^{\circ}$. This yields a catalog of 138,665 sources above the…

天体物理学 · 物理学 2009-10-28 C. M. Cress , D. J. Helfand , R. H. Becker , M. D. Gregg , R. L. White

We use the K-z relation for radio galaxies to illustrate why it has proved difficult to obtain definitive cosmological results from studies based entirely on catalogues of the brightest radio sources, e.g. 3C. To improve on this situation…

天体物理学 · 物理学 2016-01-27 Steve Rawlings , Katherine M. Blundell , Mark Lacy , Chris J. Willott , Stephen A. Eales

The power spectrum of density fluctuations measured from galaxy redshift surveys provides important constraints on models for the formation of large-scale structure. I present new results for a redshift sample of 15,000 galaxies, and review…

天体物理学 · 物理学 2007-05-23 Michael S. Vogeley

Aims. We selected two radio quasars (J1036+1326 and J1353+5725) based on their 1.4-GHz radio structure, which is dominated by a bright central core and a pair of weaker and nearly symmetric lobes at ~10" angular separation. They are…

宇宙学与河外天体物理 · 物理学 2010-12-15 D. Cseh , S. Frey , Z. Paragi , L. I. Gurvits , K. E. Gabanyi

We present the VLA-COSMOS 3 GHz Large Project based on 384 hours of observations with the Karl G. Jansky Very Large Array (VLA) at 3 GHz (10 cm) toward the two square degree Cosmic Evolution Survey (COSMOS) field. The final mosaic reaches a…

We present new deep multi-frequency radio-polarimetric images of a sample of high redshift radio galaxies (HzRGs), having redshift between 1.7 and 4.1. The radio data at 4.7 and 8.2 GHz were taken with the Very Large Array in the A…

天体物理学 · 物理学 2019-08-17 L. Pentericci , W. Van Reeven , C. L. Carilli , H. J. A. Rottgering , G. K. Miley

We present a technique to explore the radio sky into the nanoJansky regime by employing image stacking using the FIRST survey. We first discuss the non-intuitive relationship between the mean and median values of a distribution that is…

天体物理学 · 物理学 2008-11-26 Richard L. White , David J. Helfand , Robert H. Becker , Eilat Glikman , Wim deVries

This is the third of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Our data set…

宇宙学与河外天体物理 · 物理学 2015-05-14 David Rapetti , Steven W. Allen , Adam Mantz , Harald Ebeling

We study the constraints which the next generation of radio telescopes could place on the nature of dark energy, dark matter and inflation by studying the gravitational lensing of high redshift 21 cm emission, and we compare with the…

天体物理学 · 物理学 2009-06-23 R. Benton Metcalf , S. D. M. White

We present forecasts for constraints on cosmological models which can be obtained by forthcoming radio continuum surveys: the wide surveys with the LOw Frequency ARray (LOFAR), Australian Square Kilometre Array Pathfinder (ASKAP) and the…

We develop a general formalism for analysing parameter information from non-Gaussian cosmic fields. The method can be adapted to include the nonlinear effects in galaxy redshift surveys, weak lensing surveys and cosmic velocity field…

天体物理学 · 物理学 2009-10-31 Andy Taylor , Peter Watts

Gravitational wave signals from coalescing Massive Black Hole (MBH) binaries could be used as standard sirens to measure cosmological parameters. The future space based gravitational wave observatory Laser Interferometer Space Antenna…

宇宙学与河外天体物理 · 物理学 2015-03-18 Antoine Petiteau , Stanislav Babak , Alberto Sesana

This work studies the correlation among environmental density and radio AGN presence up to $z = 2$. Using data from the photometric COSMOS survey and its radio 1.4 GHz follow-up (VLA-COSMOS), a sample of radio AGNs has been defined. The…

星系天体物理 · 物理学 2016-09-09 Nicola Malavasi , Sandro Bardelli , Paolo Ciliegi , Olivier Ilbert , Lucia Pozzetti , Elena Zucca

We investigate a sample of 3412 {\it International Celestial Reference Frame} (ICRF3) extragalactic radio-loud sources with accurate positions determined by VLBI in the S/X band, mostly active galactic nuclei (AGN) and quasars, which are…

星系天体物理 · 物理学 2019-03-20 Valeri V. Makarov , Ciprian T. Berghea , Julien Frouard , Alan Fey , Henrique R. Schmitt

We present an overview of unbiased studies of diffuse extragalactic radio sources. We use a previously developed filtering technique to remove compact sources from large surveys such as WENSS, WISH, and NVSS and examine the residual diffuse…

天体物理学 · 物理学 2009-11-11 Lawrence Rudnick , Kisha M. Delain , Jeffrey A. Lemmerman