We report the discovery of a new gravitationally lensed quasar ( double ) from the Optical Gravitational Lensing Experiment ( OGLE ) identified inside the \sim 670 sq .
deg area encompassing the Magellanic Clouds .
The source was selected as one of \sim 60 ‘ ‘ red W 1 - W 2 ’ ’ mid-IR 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 < t _ { AB } < -76 days ( 90 % CL ) , with the median t _ { AB } \approx - 102 days ( 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 \approx 20.0 mag and I \approx 19.6 mag , respectively , and a lensing galaxy that becomes detectable as I \approx 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 NTT spectra .
The SED fitting with the fixed source redshift provided the estimate of the lensing galaxy redshift of z \approx 0.9 \pm 0.2 ( 90 % 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 ) .