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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 components show structure in a VLBA 8.4 GHz radio image. No further extended structure is seen in either the VLA, MERLIN or VLBA images. Hubble Space Telescope (HST) WFPC2 images in F555W and F814W show two extended objects close to the radio components, which we identify as two lens galaxies. Their colours and mass-to-light ratios seem to favour two late-type spiral galaxies at relatively high redshifts (z_d>~0.5). Faint emission is also detected at positions corresponding to the radio images. A two-lens mass model can explain the observed VLBA structure. The best fit model has a reduced chi^2 of 1.1. The relative positions of the VLBA subcomponents are reproduced within 0.08 mas, the flux density ratios within 0.19. We also reproduce the position angle and separation of the two VLBA subcomponents in A and B within the observational errors, which we consider strong evidence for the validity of the lens model. Moreover, we find a surface density axis ratio of 0.74^{+0.10}_{-0.12} for the primary lens (G1), consistent with the surface brightness axis ratio of 0.69+-0.15. Also, the surface density position angle of 4.9^{+28.2}_{-22.4} degree of G1 compares well with the -6+-13 degree position angle of the surface brightness distribution. The errors indicate the 99 per cent confidence interval.
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 separation of
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 components in
We present the discovery of CLASS B0739+366, a new gravitational lens system from the Cosmic Lens All-Sky Survey. Radio imaging of the source with the Very Large Array (VLA) shows two compact components separated by $0farcs54$, with a flux density ra
A new two-image gravitational lens system has been discovered as a result of the Cosmic Lens All-Sky Survey (CLASS). Radio observations with the VLA, MERLIN and the VLBA at increasingly higher resolutions all show two components with a flux density r
We present observations of CLASS B2108+213, the widest separation gravitational lens system discovered by the Cosmic Lens All-Sky Survey. Radio imaging using the VLA at 8.46 GHz and MERLIN at 5 GHz shows two compact components separated by 4.56 arcse