相关论文: A VLBI Study of the Gravitational Lens JVAS B0218+…

We present the results of phase-referenced VLBA+Effelsberg observations at five frequencies of the double-image gravitational lens JVAS B0218+357, made to establish the precise registration of the A and B lensed image positions. The…

We present preliminary polarisation VLBI maps of the gravitational lens system B0218+357, made at 3 different frequencies.

We observed the gravitationally lensed blazar JVAS B0218+357 with the KVN and VERA Array (KaVA) at 22, 43, and 86 GHz. The source has recently been identified as an active gamma-ray source up to GeV/TeV energy bands, rendering a unique…

We present multi-frequency radio continuum VLBI observations of the gravitational lens system B0218+357 carried out using a global VLBI network and the VLBA. The source has been observed with resolutions from 0.2 milliarcsec to 5…

In this paper we present new observations of the gravitational lens system JVAS B0218+357 made with a global VLBI network at a frequency of 8.4 GHz. Our maps have an rms noise of 30 microJy/beam and with these we have been able to image…

This is a short and biased review of gravitational lensing with emphasis on the radio and especially VLBI aspects. We briefly explain the basic idea and give a short sketch of the discovery of the first lens, before we more systematically…

We present wide-field images of the quadruple gravitational lenses B1422+231 and MGJ0414+0534 obtained from global Very Long Baseline Interferometry (VLBI) observations at 8.4 GHz on 23 November 1997. We present also a lens model for…

Measurement of the time delay between multiple images of a gravitational lens system is potentially an accurate method of determining the Hubble constant over cosmological distances. One of the most promising candidates for an application…

We present results on multifrequency Very Long Baseline Array (VLBA) monitoring observations of the double-image gravitationally lensed blazar JVAS B0218+357. Multi-epoch observations started less than one month after the gamma-ray flare…

We present results from VLBA+Effelsberg 1.7 GHz, VLBA 8.4 GHz and VLBA 15 GHz observations of the JVAS gravitational lens system B1030+074. The VLBA+Effelsberg 1.7 GHz data with 3 mas resolution reveal a detailed 60 mas jet structure in the…

We have reanalysed the 1996/1997 VLA monitoring data of the gravitational lens system JVAS B0218+357 to produce improved total flux density and polarization variability curves at 15, 8.4 and 5 GHz. This has been done using improved…

We report the discovery of a new gravitational lens system from the CLASS survey. Radio observations with the VLA, the WSRT and MERLIN show that the radio source B0850+054 is comprised of two compact components with identical spectra, a…

We present Global VLBI and HSA images of the gravitational lens B2016+112 at 18, 6 and 3.6 cm. Previous VLBI observations showed that images A and B (which are clearly lensed images of a single background source) and the elongated region C…

Gravitational lensing is a powerful tool for quantifying the mass content and distribution in distant galaxies. By using milliarcsecond angular resolution observations of radio-loud gravitationally lensed sources it is also possible to…

We present an overview of all the observations (radio - VLA, MERLIN, VLBA,EVN - and optical - WFPC2 and NICMOS -) that were initially used to confirm the gravitational lens nature of the double JVAS system B1030+074. Since the 1.56 arcsec…

We report the discovery of a new two-image gravitational lens system from the Cosmic Lens All-Sky Survey, CLASS B2319+051. Radio imaging with the Very Large Array (VLA) and Multi-Element Radio-Linked Interferometer Network (MERLIN) shows…

The four-image gravitational lens system MG0414+0534 was observed with the VLA at 1.4, 5, 8, 15, and 22 GHz. The 15 and 22 GHz images reveal structure in the components which is consistent with that seen at other wavelengths. There was no…

We present the discovery of a new gravitational lens system with two compact radio images separated by 0.701+-0.001 arcsec. The lens system was discovered in the Cosmic Lens All Sky Survey (CLASS) as a flat spectrum radio source. Both radio…

Gravitational lenses offer the possibility of accurately determining the Hubble parameter (H_0) over cosmological distances, and B0218+357 is one of the most promising systems for an application of this technique. In particular this system…

High resolution MERLIN observations of a newly-discovered four-image gravitational lens system, B0128+437, are presented. The system was found after a careful re-analysis of the entire CLASS dataset. The MERLIN observations resolve four…