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Related papers: High Frequency Peakers: The Faint Sample

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[Abridged] The nature and evolutionary properties of the faint radio population, responsible for the steepening observed in the 1.4 GHz source counts below 1 milliJy, are not yet entirely clear. Radio spectral indices may help to constrain…

The flux density scale of Perley and Butler (2013) is extended downwards to ~50 MHz by utilizing recent observations with the Karl G. Jansky Very Large Array (VLA) of 20 sources between 220 MHz and 48.1 GHz, and legacy VLA observations at…

Instrumentation and Methods for Astrophysics · Physics 2017-05-31 R. A. Perley , B. J. Butler

Knowledge of the population of radio sources in the range ~2-200 GHz is important for understanding their effects on measurements of the Cosmic Microwave Background power spectrum. We report measurements of the 30 GHz flux densities of 605…

We discuss our ATCA 18.5 and 22 GHz flux density measurements of the Southern extragalactic sources in the complete 5-GHz sample of Kuehr et al. (1981). The high-frequency (5-18.5 GHz) spectral indices of steep-spectrum sources for which we…

Astrophysics · Physics 2009-11-11 R. Ricci , I. Prandoni , G. Gruppioni , R. J. Sault , G. De Zotti

We develop an absolute flux density scale for cm-wavelength astronomy by combining accurate flux density ratios determined by the VLA between the planet Mars and a set of potential calibrators with the Rudy thermophysical emission model of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Rick A. Perley , Bryan J. Butler

Infrared-faint radio sources (IFRSs) are a rare class of object which are relatively bright at radio wavelengths but very faint at infrared and optical wavelengths. Here we present sensitive near-infrared observations of a sample of these…

We present Very Large Array (VLA) observations at 1.4 GHz and 5 GHz of a sample of 12 Quasi-stellar Objects (QSOs) at z = 3.99 to 4.46. The sources were selected as the brightest sources at 250 GHz from the recent survey of Omont et al.…

Astrophysics · Physics 2009-11-06 C. L. Carilli , F. Bertoldi , A. Omont , P. Cox , R. G. McMahon , K. G. Isaak

We present radio continuum data for 1050 B3 radio sources at 10.6 GHz. These sources constitute the B3-VLA sample which is complete down to 100 mJy at 408 MHz. The aim is the construction of a homogeneous spectral database for a large…

Astrophysics · Physics 2009-10-30 L. Gregorini , M. Vigotti , K. -H. Mack , J. Zoennchen , U. Klein

We report on sensitive radio observations made with the VLA at 8.5 GHz, centered on the Hubble Deep Field (HDF). We collected data in the A, CnB, C, DnC, and D configurations, corresponding to angular resolutions ranging from 0.3" to 10".…

We present the data and analysis of VLBI observations at 1.6, 5 and 15 GHz of a sample of faint Gigahertz Peaked Spectrum (GPS) sources selected from the Westerbork Northern Sky Survey (WENSS). The 5 GHz observations involved a global array…

Astrophysics · Physics 2016-08-30 Ignas Snellen , Richard Schilizzi , Huib-Jan van Langevelde

Since radio sources with Ultra Steep Spectra (USS; alpha <~ -1.30; S ~ nu^alpha) are efficient tracers of high redshift radio galaxies (HzRGs), we have defined three samples of such USS sources using the recently completed WENSS, TEXAS,…

Astrophysics · Physics 2011-05-23 Carlos De Breuck , Wil van Breugel , Huub Rottgering , George Miley

We report multiple epoch VLA/JVLA observations of 89 northern hemisphere sources, most with 37\,GHz flux density > 1 Jy, observed at 4.8, 8.5, 33.5, and 43.3 GHz. The high frequency selection leads to a predominantly flat spectrum sample,…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-21 Noah Kurinsky , Anna Sajina , Bruce Partridge , Steve Myers , Xi Chen , Marcos López-Caniego

In order to determine the relationship between the faint X-ray and faint radio source populations, and hence to help understand the X-ray and radio emission mechanisms in those faint source populations, we have made a deep 1.4GHz Very Large…

Astrophysics · Physics 2009-11-10 N. Seymour , I. M. McHardy , K. F. Gunn

We present the results of optical spectroscopy of two flux-density-limited samples of radio sources selected at frequencies of 38 and 151 MHz in the same region around the North Ecliptic Cap, the 8C-NEC and 7C-III samples respectively. Both…

High-redshift quasars are important to study galaxy and active galactic nuclei (AGN) evolution, test cosmological models, and study supermassive black hole growth. Optical searches for high-redshift sources have been very successful, but…

Study of high-redshift radio galaxies (HzRGs) can shed light on the active galactic nuclei (AGNs) evolution in massive elliptical galaxies. The vast majority of observed high-redshift AGNs are quasars, and there are very few radio galaxies…

The radio bright zone (RBZ) at the Galactic center has been observed with the JVLA in the A, B and C array configurations at 5.5 and 9 GHz. With a procedure for high-dynamic range imaging developed on CASA, we constructed deep images a…

High Energy Astrophysical Phenomena · Physics 2020-10-26 Jun-Hui Zhao , Mark R. Morris , W. M. Goss

Radio surveys with the Australia Telescope Compact Array have been carried out at 1.4 and 2.4 GHz with a limiting flux of 0.2 mJy at each frequency in the Marano Field, in which deep optical and X-ray (ROSAT) data are also available. In…

Spectra have been obtained with the Infrared Spectrograph on the Spitzer Space Telescope for 18 optically faint sources (R > 23.9,mag) having f(nu) (24um) > 1.0,mJy and having radio detections at 20 cm to a limit of 115 microJy. Sources are…

Astrophysics · Physics 2009-11-13 D. W. Weedman , E. Le Floc'h , S. J. U. Higdon , J. L. Higdon , J. R. Houck

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