We have conducted a search for z≃7 Lyman break galaxies over 8.2 square degrees of near-infrared imaging from the VISTA Deep Extragalactic Observations (VIDEO) survey in the XMM-Newton - Large Scale Structure (XMM-LSS) and the Extended Chandra Deep Field South (ECDF-S) fields. Candidate galaxies were selected from a full photometric redshift analysis down to a Y+J depth of 25.3 (5σ), utilizing deep auxiliary optical and Spitzer/IRAC data to remove brown dwarf and red interloper galaxy contaminants. Our final sample consists of 28 candidate galaxies at 6.5≤z≤7.5 with −23.5≤MUV≤−21.6. We derive stellar masses of 9.1≤log10(M/M⊙)≤10.9 for the sample, suggesting that these candidates represent some of the most massive galaxies known at this epoch. We measure the rest-frame UV luminosity function (LF) at z≃7, confirming previous findings of a gradual decline in number density at the bright-end (MUV5 samples, our results further support little evolution in the very bright-end of the rest-frame UV LF from z=5−10, potentially signalling a lack of mass quenching and/or dust obscuration in the most massive galaxies in the first Gyr.
- Astrophysics - Astrophysics of Galaxies