中文
相关论文

相关论文: Faint Radio Sources in the NOAO Bootes Field. VLBA…

200 篇论文

We have conducted a deep, very long baseline interferometry (VLBI) observation at 1.4 GHz of an area of sky located within the NOAO Bootes field, using the NRAO VLBA and 100-m Green Bank Telescope. Applying wide-field VLBI techniques, a…

天体物理学 · 物理学 2009-11-10 M. A. Garrett , J. M. Wrobel , R. Morganti

We study the faint radio population using wide-field very long baseline interferometry (VLBI) observations of 2865 known radio sources in the Cosmic Evolution Survey (COSMOS) field. The main objective of the project was to determine where…

With the goal of investigating the nature and the environment of the faint radio sources (at mJy level), here are presented results of X-ray dentifications of Faint Imaging Radio Survey at Twenty centimetres (FIRST) in the 9 square degrees…

宇宙学与河外天体物理 · 物理学 2015-05-13 Khadija EL Bouchefry

We have used VLBA fringe visibility data obtained at 15 GHz to examine the compact structure in 250 extragalactic radio sources. For 171 sources in our sample, more than half of the total flux density seen by the VLBA remains unresolved on…

Radio-loud active galactic nuclei (AGNs), hosting powerful relativistic jet outflows, provide an excellent laboratory for studying jet physics. Very long baseline interferometry (VLBI) enables high-resolution imaging on milli-arcsecond…

高能天体物理现象 · 物理学 2018-02-07 X. -P. Cheng , T. An , X. -Y. Hong , J. Yang , P. Mohan , K. I. Kellermann , M. L. Lister , S. Frey , W. Zhao , Z. -L. Zhang , X. -C. Wu , X. -F. Li , Y. -K. Zhang

We observed with the VLBA at 2.3 and 8.6 GHz a complete flux-density limited sample of 482 radio sources with declination >+75 degrees brighter than 200 mJy at 1.4 GHz drawn from the NVSS catalog. 34% of the sources show parsec-scale…

星系天体物理 · 物理学 2021-02-01 Alexander V. Popkov , Yuri Y. Kovalev , Leonid Y. Petrov , Yuri A. Kovalev

The NRAO Very Long Baseline Array (VLBA) was used at 1.4 GHz to image 20 compact sources in the inner 1-degree radius of the Spitzer VLA First-Look Survey. Twelve sources were detected with the VLBA, with peak flux densities above 2 mJy at…

天体物理学 · 物理学 2009-11-10 J. M. Wrobel , M. A. Garrett , J. J. Condon , R. Morganti

We present preliminary results from a VLBI survey at $\lambda=6 $cm of a sample of 35 sources with flux densities of 2 - 100 mJy. These sources were selected from the VLA FIRST survey at $\lambda = 20 $cm, in a 3 degree field around the…

天体物理学 · 物理学 2009-10-31 S. T. Garrington , M. A. Garrett , A. Polatidis

The first Fermi-LAT High-energy source catalog (1FHL), containing gamma-ray sources detected above 10 GeV, is an ideal sample to characterize the physical properties of the most extreme gamma-ray sources. We investigate the pc scale…

高能天体物理现象 · 物理学 2016-10-19 R. Lico , M. Giroletti , M. Orienti , F. D'Ammando

We present very long baseline interferometry (VLBI) observations of 179 radio sources in the COSMOS field with extremely high sensitivity using the Green Bank Telescope (GBT) together with the Very Long Baseline Array (VLBA) (VLBA+GBT) at…

We present preliminary results from the deepest VLBI observations yet conducted. VLBA+GBT 1.4 GHz observations of a region within NOAO-N, reach an r.m.s. noise level of 9 microJy per beam. Three sources are clearly detected (> 7 sigma)…

天体物理学 · 物理学 2009-11-07 M. A. Garrett , J. M. Wrobel , R. Morganti

We observed 17 nearby low luminosity FR I radio galaxies using the NRAO Very Long Baseline Array (VLBA) at 1.67 GHz, as part of a multi-wavelength study of a complete sample of 21 sources selected by radio flux density from the Uppsala…

天体物理学 · 物理学 2009-10-31 Chun Xu , Stefi A. Baum , Christopher P. O'Dea , J. M. Wrobel , J. J. Condon

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…

天体物理学 · 物理学 2016-08-30 Ignas Snellen , Richard Schilizzi , Huib-Jan van Langevelde

[Abridged] Sub-mm observations of the William Herschel Deep Field using LABOCA revealed possible counterparts for 2 X-ray absorbed QSOs. The aim here is to exploit EVLA imaging at 8.4 GHz to establish the QSOs as radio/sub-mm sources. The…

宇宙学与河外天体物理 · 物理学 2012-09-24 I. Heywood , R. M. Bielby , M. D. Hill , N. Metcalfe , S. Rawlings , T. Shanks , O. M. Smirnov

We report on the first wide-field, very long baseline interferometry (VLBI) survey at 90 cm. The survey area consists of two overlapping 28 deg^2 fields centred on the quasar J0226+3421 and the gravitational lens B0218+357. A total of 618…

天体物理学 · 物理学 2009-11-13 Emil Lenc , Mike A. Garrett , Olaf Wucknitz , James M. Anderson , Steven J. Tingay

A 20-hour VLBI observation with the NRAO VLBA and GBT in the NOAO Bootes field reaches an rms noise of 9 microJy per beam at 1.4 GHz. Three sources were detected at 10-milliarcsecond resolution within the GBT primary beam of FWHM 8.6',…

天体物理学 · 物理学 2007-05-23 M. A. Garrett , J. M. Wrobel , R. Morganti

Aims. We have analysed VLBA 92cm archive data of 44 extragalactic sources in order to identify early targets and potential calibrator sources for the LOFAR radio telescope and the RadioAstron space VLBI mission. Some of these sources will…

宇宙学与河外天体物理 · 物理学 2015-05-13 H. Rampadarath , M. A. Garrett , A. Polatidis

In this article we present deep, high-resolution radio interferometric observations at 153 MHz to complement the extensively studied NOAO Bootes field. We provide a description of the observations, data reduction and source catalog…

宇宙学与河外天体物理 · 物理学 2015-05-30 H. T. Intema , R. J. van Weeren , H. J. A. Rottgering , D. V. Lal

We present the observational results from the 43-GHz Very Long Baseline Array (VLBA) observations of 124 compact radio-loud active galactic nuclei (AGNs) that were conducted between 2014 November and 2016 May. The typical dimensions of the…

‹ 上一页 1 2 3 10 下一页 ›