The VISTA EXtension to Auxiliary Surveys (VEXAS) project aims at providing photometric catalogues with the most uniform spatial coverage, in the multi-wavelength sky for various scientific uses such as object classification (e.g., quasars, galaxies, and stars; high-z galaxies, white dwarfs), photometric redshifts of large galaxy samples and identification of exotic objects (e.g., extremely red objects and lensed quasars). This first data release covers the Southern Galactic Hemisphere (SGH) and objects below the Galactic plane, b < -20 degrees.
Data Release 1: VISTA EXtension to Auxiliary Surveys (VEXAS)
It comprises 7 cross-matched multi-wavelength photometric catalogues where each object has a match in at least 2 surveys, plus reliable photometry in at least 3 bands. In the current release, the 2 main extragalactic surveys on the ESO Visible and Infrared Survey Telescope for Astronomy (VISTA) - the VISTA Hemisphere Survey (VHS) and the VISTA Kilo Degree Infrared Galaxy Survey (VIKING) - are cross-matched with several high legacy wide-sky photometric surveys in the optical, X-ray and radio domain. Finally, the released catalogue includes the cross-matching with spectroscopic data from the Sloan Digital Sky Survey and the 6 degrees Field Galaxy Survey. As of today, the VEXAS catalogues are the widest and deepest public optical-to-infrared photometric and spectroscopic catalogues covering the southern hemisphere.
The VEXAS catalogues are now available via the ESO Catalogue Query Interface with a detailed release description document. Also see Spiniello & Agnello (2019, A&A, 630) for more details