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Related papers: High frequency peakers. I. The bright sample

200 papers

The Very Large Array Sky Survey (VLASS) is observing the entire sky north of $-40^{\circ}$ in the S-band ($2<\nu<4\,$GHz), with the highest angular resolution ($2''.5$) of any all-sky radio continuum survey to date. VLASS will cover its…

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…

We report the results of multifrequency-VLBI observations of GHz-Peaked-Spectrum (GPS) radio sources. The VLBI structure and component spectra of some GPS sources are presented. Our VLBI results show that about 80% of the GPS galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-20 X. Liu , H. -G Song , L. Cui

The main aim is to investigate the possibility of a high frequency turn-over in the radio spectrum of pulsars. Using the GMRT, multi-frequency flux density measurements of several candidate pulsars have been carried out and their spectra…

Astrophysics · Physics 2009-11-11 J. Kijak , Y. Gupta , K. Krzeszowski

We present a new sample of 84 large angular size radio galaxies selected from the NRAO VLA Sky Survey. Radio sources with declination above +60 degrees, total flux density greater than 100 mJy at 1.4 GHz and angular size larger than 4…

Astrophysics · Physics 2009-11-06 L. Lara , W. D. Cotton , L. Feretti , G. Giovannini , J. M. Marcaide , I. Marquez , T. Venturi

We present VLBA observations at 15 GHz of ten GHz Peaked Spectrum (GPS) radio sources. The cores are often difficult or impossible to locate. When likely cores are found, they account for a small fraction of the flux density in GPS galaxies…

Astrophysics · Physics 2009-11-07 C. Stanghellini , D. Dallacasa , C. P. O'Dea , S. A. Baum , R. Fanti , C. Fanti

We use the recent releases of sensitive VLA/LOFAR large-area surveys at 340 MHz and 54 MHz, in conjunction with the 1.4 GHz NVSS, to accurately determine the `spectral index - flux density relation' ($\alpha$ - S) for extragalactic radio…

Astrophysics of Galaxies · Physics 2023-07-05 Pratik Dabhade , Gopal-Krishna

We present total flux densities of 1049 radio sources in the frequency range from 151 MHz to 10.6 GHz. These sources belong to the B3-VLA sample, which is complete down to 100 mJy at 408 MHz. The data constitute a homogeneous spectral…

Astrophysics · Physics 2009-10-31 M. Vigotti , L. Gregorini , U. Klein , K. -H. Mack

We have studied a sample of 296 faint (> 0.5 mJy) radio sources selected from an area of the Tenth Cambridge (10C) survey at 15.7 GHz in the Lockman Hole. By matching this catalogue to several lower frequency surveys (e.g. including a deep…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-06 I. H. Whittam , J. M. Riley , D. A. Green , M. J. Jarvis , I. Prandoni , G. Guglielmino , R. Morganti , H. J. A. Röttgering , M. A. Garrett

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

Extended radio emission detected around a sample of GHz Peaked Spectrum (GPS) radio sources is discussed. Evidence for extended emission which is related to the GPS source is found in 6 objects out of 33. Three objects are associated with…

Astrophysics · Physics 2009-11-11 C. Stanghellini , C. P. O'Dea , D. Dallacasa , P. Cassaro , S. A. Baum , R. Fanti , C. Fanti

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

We point out that the remarkable linearity of the ultra-steep radio spectra of high redshift radio galaxies reflects a previously reported general trend for powerful radio galaxies, according to which the spectral curvature is lesser for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Gopal-Krishna , Mukul Mhaskey , A. Mangalam

Individual giant radio pulses (GRPs) from the Crab pulsar last only a few microseconds. However, during that time they rank among the brightest objects in the radio sky reaching peak flux densities of up to 1500 Jy even at high radio…

Astrophysics · Physics 2007-05-23 A. Jessner , A. Slowikowska , B. Klein , H. Lesch , C. H. Jaroschek , G. Kanbach , T. H. Hankins

A sample of 123 radio sources that exhibit significant variations at 1.4 GHz on a seven year base-line has been created using FIRST VLA B-array data from 1995 and 2002 on a strip at dec=0 near the south Galactic cap. This sample spans the…

Astrophysics · Physics 2009-11-10 W. H. de Vries , R. H. Becker , R. L. White , D. J. Helfand

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 present sensitive radio continuum images at high resolution of 37 radio galaxies at z > 2. The observations were made with the Very Large Array (VLA) at 4.7 GHz and 8.2 GHz, with typical resolutions of 0.45'' and 0.25'', respectively.…

We present basic observational data on the 6C** sample. This is a new sample of radio sources drawn from the 151 MHz 6C survey, which was filtered with radio criteria chosen to optimize the chances of finding radio galaxies at z > 4. The…

Multifrequency Very Long Baseline Array (VLBA) observations were performed to study the radio morphology and the synchrotron spectra of four high frequency peaking radio sources. They are resolved in several compact components and the radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 M. Orienti , D. Dallacasa

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