Kostrzewa-Rutkowska, Z.Kozlowski, S.Lemon, C.Anguita, T.Greiner, J.Auger, M.W.Wyrzykowski, L.Apostolovski, Y.Bolmer, J.Udalski, A.Szymański, M.K.Soszyński, I.Poleski, R.Pietrukowicz, P.Skowron, J.Mróz, P.Ulaczyk, K.Pawlak, M.2018-09-242018-09-242018-05Monthly Notices of the Royal Astronomical Society, 476(1), pp. 663-672.0035-8711DOI: 10.1093/mnras/sty259http://repositorio.unab.cl/xmlui/handle/ria/7043Indexación: Scopus; Web of Science.We report the discovery of a new gravitationally lensed quasar (double) from the Optical Gravitational Lensing Experiment (OGLE) identified inside the ~670deg2 area encompassing the Magellanic Clouds. The source was selected as one of ~60 'red W1-W2' mid-infrared objects from WISE and having a significant amount of variability in OGLE for both two (or more) nearby sources. This is the first detection of a gravitational lens, where the discovery is made 'the other way around', meaning we first measured the time delay between the two lensed quasar images of -132 < tAB < -76 d (90 per cent CL), with the median tAB ~-102 d (in the observer frame), and where the fainter image B lags image A. The system consists of the two quasar images separated by 1.5 arcsec on the sky, with I ~20.0mag and I ~19.6mag, respectively, and a lensing galaxy that becomes detectable as I ~21.5 mag source, 1.0 arcsec from image A, after subtracting the two lensed images. Both quasar images show clear AGN broad emission lines at z=2.16 in the New Technology Telescope spectra. The spectral energy distribution (SED) fitting with the fixed source redshift provided the estimate of the lensing galaxy redshift of z ~0.9 ± 0.2 (90 per cent CL), while its type is more likely to be elliptical (the SED-inferred and lens-model stellar mass is more likely present in ellipticals) than spiral (preferred redshift by the lens model). © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.enGravitational lensing: StrongMethods: ObservationalQuasars: GeneralArtículo