A submillimetre galaxy at z=4.76 in the LABOCA survey of the Extended Chandra Deep Field South

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We report on the identification of the highest redshift submm-selected source currently known: LESSJ033229.4-275619.

• This source was detected in the Large Apex BOlometer CAmera (LABOCA) Extended Chandra Deep Field South (ECDFS) Submillimetre Survey (LESS), a sensitive 870-um survey (~1.2-mJy rms) of the full 30'x30' ECDFS with the LABOCA camera on the Atacama Pathfinder EXperiment (APEX) telescope.
• The submm emission is identified with a radio counterpart for which optical spectroscopy provides a redshift of z=4.76.
• We show that the bolometric emission is dominated by a starburst with a star formation rate of ~1000 Msun/yr, although we also identify a moderate luminosity Active Galactic Nucleus (AGN) in this galaxy.