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arXiv · 1805.01939

Another Quadruply Lensed Quasar from the VST-ATLAS Survey

P. L. Schechter·T. Anguita·N. D. Morgan·M. Read·T. Shanks
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Abstract

We report the quadruple nature of the source WISE 025942.9-163543 as observed in the VST-ATLAS survey. Spectra of the two brightest images show quasar emission lines at z=2.16. The system was discovered by splitting ATLAS "cutouts" of WISE sources with W1-W2 > 0.7, when possible, into three components. Followup Magellan images were used to obtain astrometry and g and i photometry, with i=18.78 and 19.73, respectively, for the brightest and faintest components. Absorption lines are observed at z=0.905 but there is little evidence for a lensing galaxy after PSF fitting and subtraction. Saha and Williams (2003) would classify ATLAS 0259-1635 as a short-axis quad. The larger and smaller diameters are 1.57 and 1.32 arcseconds, respectively. Modeling the lensing galaxy as a singular isothermal sphere with external shear, the largest and smallest predicted magnifications are 10.8 and 6.4 respectively.

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P. L. Schechter, T. Anguita, N. D. Morgan, M. Read, T. Shanks. 2018-05-04. Another Quadruply Lensed Quasar from the VST-ATLAS Survey. https://doi.org/10.3847/2515-5172%2Faac1bf

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