A VLT colour image of the optical Einstein ring 0047 – 2808 ?
نویسندگان
چکیده
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 Lyα emission at 5589Å, gravita-tionally 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 Lyα 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 ∼ 13 h for the deflector galaxy. We have combined the VLT B–band and Lyα narrow–band images with a K–band image obtained at UKIRT to produce a deep colour image of the system.
منابع مشابه
VLT colour image of the optical Einstein ring 0047 – 2808 ⋆
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 Lyα emission at 5589Å, 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 Lyα narrow–band image allows much improved co...
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We present optical and near–infrared spectroscopic observations of the optical Einstein ring 0047–2808. We detect both [OIII] lines λλ4959, 5007 near ∼ 2.3μ, confirming the redshift of the lensed source as z = 3.595. The Lyα line is redshifted relative to the [OIII] line by 140± 20 km s. Similar velocity shifts have been seen in nearby starburst galaxies. The [OIII] line is very narrow, 130 km ...
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