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A VLT colour image of the optical Einstein ring 0047-2808

S. J. Warren·G. F. Lewis·P. C. Hewett·P. Moller·P. Shaver·A. Iovino
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Abstract

The optical Einstein ring 0047-2808 was imaged by the VLT UT1 during the science verification programme. The ring is the image of a high-redshift z=3.595 star-forming galaxy, with strong Ly-alpha emission at 5589A, gravitationally lensed by a massive early-type galaxy at z=0.485. Relative to earlier NTT data the high signal-to-noise ratio of the VLT Ly-alpha narrow-band image allows much improved constraints to be placed on the surface-brightness profile of the source and on the mass, leading to a measured mass-to-light ratio of M/L(B)~13h for the deflector galaxy. We have combined the VLT B-band and Ly-alpha narrow-band images with a K-band image obtained at UKIRT to produce a deep colour image of the system.

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S. J. Warren, G. F. Lewis, P. C. Hewett, P. Moller, P. Shaver, A. Iovino. 1999-01-20. A VLT colour image of the optical Einstein ring 0047-2808. https://arxiv.org/abs/astro-ph/9901271

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