VHS - VISTA Hemisphere Survey

The VISTA Hemisphere Survey (VHS; ESO Programme ID: 79.A-2010) is a wide field near infrared survey, which when combined with other VISTA public surveys results in coverage of the whole southern celestial hemisphere (Declination < 0◦; ∼ 20,000deg2) to a depth 30 times fainter than 2MASS/DENIS in at least two wavebands (J and Ks), with a minimum exposure time of 60 seconds per waveband and a median 5σ point source depth of AB = 20.8 and 20.0 in J and Ks wavebands respectively. In the South Galactic Cap, around 4500 deg2 is being imaged deeper with an exposure time per coadded image of 120–240 seconds in J, 120 seconds in Ks and partial coverage in H band with an exposure time of 120 seconds, producing median 5σ point limits of AB = 21.4, 20.7 and 20.3 in J, H and Ks respectively. In this 4500 deg2 region of sky deep multi-band optical (grizY) imaging data is being provided by the Dark Energy Survey (DES). The remainder of the high galactic latitude (|b| > 30◦) sky is being imaged in Y, J, Ks for 60–120 sec per band with median 5σ point source limits of AB = 21.1, 20.8 and 20.0 and partial coverage in H with a median 5σ point source limit of 20.3. This region is being imaged in the optical wavebands (ugriz) by the the VST ATLAS survey. The median 5σ point source depths for the total survey area coadd images in this data release is AB=21.1, 20.8, 20.5, 20.0 in Y, J, H and Ks wavebands respectively.