English
Related papers

Related papers: High-redshift QSOs in the FIRST survey

200 papers

We present optical and/or near-IR images of 128 ultra steep spectrum (USS) radio sources. Roughly half of the objects are identified in the optical images (R <~ 24), while in the near-IR images, >94% are detected at K<~ 22. The mean…

This paper introduces a new program to find high-redshift radio galaxies in the southern hemisphere through ultra-steep spectrum (USS) selection. We define a sample of 234 USS radio sources with spectral indices alpha_408^843 < -1.0 and…

Astrophysics · Physics 2009-11-13 J. W. Broderick , J. J. Bryant , R. W. Hunstead , E. M. Sadler , T. Murphy

We present a multi-wavelength study of Extremely Red Objects (EROs) employing deep RIzJHK photometry of a 8.5'x8.5' region to identify 68 EROs with R-K>5.3 and K<20.5 (5-sigma). This is combined with an extremely deep 1.4-GHz radio map…

Astrophysics · Physics 2009-11-07 Ian Smail , F. N. Owen , G. E. Morrison , W. C. Keel , R. J. Ivison , M. J. Ledlow

We present the initial sample of redshifts for 3,839 galaxies in the MeerKAT DEEP2 field -- the deepest $\sim$1.4\,GHz radio field yet observed. Using a spectrophotometric technique combining coarse optical spectra with broadband…

Astrophysics of Galaxies · Physics 2024-04-24 A. M Matthews , D. D. Kelson , A. B. Newman , F. Camilo , J. J. Condon , W. D. Cotton , M. Dickinson , T. H. Jarrett , M. Lacy

We present a sample of 1317 Infrared-Faint Radio Sources (IFRSs) that, for the first time, are reliably detected in the infrared, generated by cross-correlating the Wide-Field Infrared Survey Explorer (WISE) all-sky survey with major radio…

We present a catalogue of 349 giant radio sources (GRSs including both galaxies and quasars). The database contains all giants known to date from the literature. These GRSs cover the redshift range of 0.016$<$z$<$3.22 and include radio…

Astrophysics of Galaxies · Physics 2018-10-10 A. Kuźmicz , M. Jamrozy , K. Bronarska , K. Janda-Boczar , D. J. Saikia

While unobscured and radio-quiet active galactic nuclei are regularly being found at redshifts $z > 6$, their obscured and radio-loud counterparts remain elusive. We build upon our successful pilot study, presenting a new sample of…

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Dharam Vir Lal , Luis C. Ho

From examination of only 4 deg^2 of sky in the NOAO Deep Wide-Field Survey (NDWFS) region, we have identified the first radio-loud quasar at a redshift z>6. The object, FIRST J1427385+331241, was discovered by matching the FLAMEX IR survey…

Astrophysics · Physics 2011-02-11 Ian D. McGreer , Robert H. Becker , David J. Helfand , Richard L. White

Using a combination of near-infrared and optical photometry, along with multi-object spectroscopy, we have confirmed the existence of a high-redshift cluster of galxies at z = 0.96. The cluster was found using a wide-angle tailed radio…

Using a recently completed survey of faint (sub-mJy) radio sources, selected at 1.4 GHz, a dust-free estimate of the local star formation rate (SFR) is carried out. The sample is 50% complete to 0.2 mJy, with over 50% of the radio sources…

Astrophysics · Physics 2009-10-31 B. Mobasher , L. Cram , A. Georgakakis , A. Hopkins

We present a spectroscopic survey using the MMT/Hectospec fiber spectrograph of 24 micron sources selected with the Spitzer Space Telescope in the Spitzer First Look Survey. We report 1296 new redshifts for 24 micron sources, including 599…

We test the hypothesis whether high redshift QSOs would preferentially appear in small groups or pairs, and if they are associated with massive, young clusters. We carried out a photometric search for \Ly emitters on scales $\lesssim 10…

Astrophysics · Physics 2009-11-07 L. Infante , J. Varela , M. Moles , G. Hertling , A. Garcia , F. Menanteau

We present a new measurement of the space density of high redshift (3.0<z<4.5), X-ray selected QSOs obtained by exploiting the deep and uniform multiwavelength coverage of the COSMOS survey. We have assembled a statistically large (40…

We present the first results from a pilot study to search for distant radio galaxies in the southern hemisphere (delta < -32). Within a 360 deg^2 region of sky, we define a sample of 76 ultra-steep spectrum (USS) radio sources from the 843…

Unlike at lower redshift, where there is a 40% detection rate, surveys for 21-cm absorption arising within the hosts of z > 1 radio galaxies and quasars have been remarkably unsuccessful. Curran et al.(2008) suggest that this is due to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 S. J. Curran , M. T. Whiting , E. M. Sadler , C. Bignell

We present deep near-infrared $K_{\rm s}$-band imaging for 35 of the 53 sources from the high-redshift ($z > 2$) radio galaxy candidate sample defined in Broderick et al. (2022). These images were obtained using the High-Acuity Widefield…

We present the results of a search for red QSOs using a selection based on optical imaging from SDSS and near-infrared imaging from UKIDSS. For a sample of 58 candidates 46 (79%) are confirmed to be QSOs. The QSOs are predominantly…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-04 J. P. U. Fynbo , J. -K. Krogager , B. Venemans , P. Noterdaeme , M. Vestergaard , P. Moller , C. Ledoux , S. Geier

We have obtained low resolution (~20 Angstrom FWHM) slit spectra of 10 quasar candidates located within one degree of the z = 2.181 quasar Q0122-380 with the objective of searching for signs of large scale structure matching the intervening…

Astrophysics · Physics 2007-05-23 R. A. Jansen , P. Jakobsen

We show that the use of red colour as the basis for selecting candidate high redshift dusty galaxies from surveys made with Herschel has proved highly successful. The highest redshift such object, HFLS3, lies at z=6.34 and numerous other…

‹ Prev 1 4 5 6 7 8 10 Next ›