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arXiv · 1908.11392

VEXAS: the VISTA EXtension to Auxiliary Surveys -- Data Release 1: the Southern Galactic Hemisphere

C. Spiniello·A. Agnello
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Abstract

We present the first public data release of the VISTA EXtension to Auxiliary Surveys (VEXAS), comprising of 9 cross-matched multi-wavelength photometric catalogs where each object has a match in at least two surveys. We aim at a spatial coverage as uniform as possible in the multi-wavelength sky, with the purpose of providing the astronomical community with reference magnitudes and colours for various scientific uses, including: object classification (e.g. quasars, galaxies, and stars; high-z galaxies, white dwarfs, etc.); photometric redshifts of large galaxy samples; searches of exotic objects such as, for example, extremely red objects and lensed quasars. We have cross-matched the wide-field VISTA catalogs (the VISTA Hemisphere Survey and the VISTA Kilo Degree Infrared Galaxy Survey) with the AllWISE mid-infrared Survey, requiring that a match exists within 10 arcsec. We have further matched this table with X-Ray and radio data (ROSAT, XMM, SUMSS). We also performed a second cross-match between VISTA and AllWISE, with a smaller matching radius (3"), including WISE magnitudes. We have then cross-matched this resulting table ($\approx138\times10^6$ objects) with three photometric wide-sky optical deep surveys (DES, SkyMapper, PanSTARRS). We finally include matches to objects with spectroscopic follow-up by the SDSS and 6dFGS. To demonstrate the power of all-sky multi-wavelength cross-match tables, we show two examples of scientific applications of VEXAS, in particular using the publicly released tables to discover strong gravitational lenses (beyond the reach of previous searches), and to build a statistically large sample of extremely red objects. The VEXAS catalog is currently the widest and deepest, public, optical-to-IR photometric and spectroscopic database in the Southern Hemisphere.

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C. Spiniello, A. Agnello. 2019-08-29. VEXAS: the VISTA EXtension to Auxiliary Surveys -- Data Release 1: the Southern Galactic Hemisphere. https://doi.org/10.1051/0004-6361/201936311

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