中文
相关论文

相关论文: The Sixth VLBA Calibrator Survey: VCS6

200 篇论文

We defined a sub-sample of twelve GPS sources which have not been observed with the VLBI before, from the Parkes half-Jansky sample, and carried out VLBI observations at 1.6 GHz and 5 GHz with the European VLBI Network (EVN) in 2006 and…

宇宙学与河外天体物理 · 物理学 2011-01-25 L. Cui , X. Liu , J. Liu , H. -G. Song , Z. Ding

We have obtained 8.4 GHz VLBA observations of a 31-GHz complete sample of ~100 sources between 10 and 100 mJy. The main goals of these observations are: to determine the angular size, radio spectra and identification for a weak sample of…

天体物理学 · 物理学 2008-06-19 W. A. Majid , E. B. Fomalont , D. S. Bagri

We present the description and early results of the mJy Imaging VLBA Exploration at 20 cm (mJIVE-20). mJIVE-20 is a large project on the Very Long Baseline Array which uses "filler" time to systematically inspect a large sample of mJy radio…

宇宙学与河外天体物理 · 物理学 2015-06-17 A. T. Deller , E. Middelberg

The VLA-COSMOS Large Project has imaged the 2 sq.deg. COSMOS field with a resolution of 1.5 arcsec and a sensitivity of about 11 microJy (1 sigma) yielding to a catalog of about 3600 radio sources. In this paper we present a further…

天体物理学 · 物理学 2009-11-13 M. Bondi , P. Ciliegi , E. Schinnerer , V. Smolcic , K. Jahnke , C. Carilli , G. Zamorani

Very long baseline interferometry (VLBI) technique allows us to determine positions of thousands of radio sources using the absolute astrometry approach. I have investigated the impact of a selection of observing frequencies in a range from…

天体物理仪器与方法 · 物理学 2024-05-14 Leonid Petrov

Deep radio surveys of extragalactic legacy fields trace a large range of spatial and brightness temperature sensitivity scales, and therefore have differing biases to radio-emitting physical components within galaxies. This is particularly…

In this study we attempt to assess the possibility of detection of variable sources using the data of the 7.6-cm wavelength surveys carried out on the RATAN-600 radio telescope in the period from 1980 through 1994. Objects selected…

星系天体物理 · 物理学 2014-09-15 E. K. Majorova , O. P. Zhelenkova

Aims: We computed a celestial reference frame (CRF) from Very Long Baseline Interferometry (VLBI) Global Observing System (VGOS) data after five years of regular observations (155 multi-baseline 24-hour VGOS sessions until 2024.0). In this…

天体物理仪器与方法 · 物理学 2024-11-25 Hana Krasna , Christopher S. Jacobs , Matthias Schartner , Patrick Charlot

Very Long Baseline Interferometry (VLBI) combines the signals of telescopes distributed across thousands of kilometres to provide some of the highest angular resolution images of astrophysical phenomena. Due to computational expense,…

天体物理仪器与方法 · 物理学 2025-04-30 Jack F. Radcliffe , J. P. McKean , C. Herbé-George , L. Coetzer , T. Matsepane

The Caltech-Jodrell Bank very long baseline interferometry (VLBI) Surveys give detailed 5 GHz VLBI images of several hundred milliarcsecond (mas) radio sources, and the full width at half-maximum angular sizes of the corresponding compact…

天体物理学 · 物理学 2009-11-13 J. C. Jackson

Radio-loud quasars at high redshift (z > 4) are rare objects in the Universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position.…

We report a serendipitous detection of rapid, large amplitude flux density variations in the highly core-dominated, flat-spectrum radio quasar 1156+295 during an observing session at the Very Long Baseline Array (VLBA). The source was…

天体物理学 · 物理学 2008-10-06 T. Savolainen , Y. Y. Kovalev

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed contemporaneously by the Very Long Baseline Array (VLBA). In total, 232 sources were observed with…

For Very Long Baseline Interferometry (VLBI), the fringe spacing is extremely narrow compared to the field of view imposed by the primary beam of each element. This means that an extremely large number of resolution units can potentially be…

天体物理仪器与方法 · 物理学 2013-02-26 John S. Morgan , F. Mantovani , A. T. Deller , W. Brisken , W. Alef , E. Middelberg , M. Nanni , S. J. Tingay

We present the results of a recent re-reduction of the data from the Very Large Array (VLA) Low-frequency Sky Survey (VLSS). We used the VLSS catalog as a sky model to correct the ionospheric distortions in the data and create a new set of…

天体物理仪器与方法 · 物理学 2015-06-19 W. M. Lane , W. D. Cotton , S. van Velzen , T. E. Clarke , N. E. Kassim , J. F. Helmboldt , T. J. W. Lazio , A. S. Cohen

The CONT14 campaign with state-of-the-art VLBI data has observed the source 0642+449 with about one thousand observables each day during a continuous observing period of fifteen days, providing tens of thousands of closure delays---the sum…

天体物理仪器与方法 · 物理学 2016-11-09 Ming H. Xu , Robert Heinkelmann , James M. Anderson , Julian Mora-Diaz , Harald Schuh , Guang L. Wang

We report the results of a successful 12 hour 22 GHz VLBI experiment using a heterogeneous network that includes radio telescopes of the Long Baseline Array (LBA) in Australia and several VLBI stations that regularly observe in geodetic…

The space astrometry mission GAIA will construct a dense optical QSO-based celestial reference frame. For consistency between the optical and radio positions, it will be important to align the GAIA frame and the International Celestial…

天体物理学 · 物理学 2009-11-13 Geraldine Bourda , Patrick Charlot , Richard Porcas , Simon Garrington

We present $4-12$ GHz in-band spectral energy distributions with accompanying 6 GHz and 10 GHz imaging results for a volume-complete sample ($<40$ Mpc) of hard X-ray selected active galactic nuclei (AGNs) observed with the Karl G. Jansky…