Abstract
| - We present optical R-band light curves of five SDSS double QSOs (SDSS J0903+5028, SDSS J1001+5027, SDSS J1206+4332, SDSS J1353+1138, SDSS J1335+0118) obtained from monitoring at the Nordic Optical Telescope (NOT) between September 2005 and September 2007. We also present analytical and pixelated modeling of the observed systems. For SDSS J1206+4332, we measured the time delay to be $\Delta \tau = 116^{+ 4 }_{-5}$ days, which, for a singular isothermal ellipsoid model, corresponds to a Hubble constant of $73^{\rm +3}_{-4}$ km s -1 Mpc -1. Simultaneous pixelated modeling of five other systems for which a time delay has now been previously measured at the NOT leads to H0 = $61.5^{\rm +8}_{-4}$ km s -1 Mpc -1. Finally, by comparing light curves of the two images of each system, suitably shifted by the predicted or observed time-delays, we found no evidence of microlensing variability over the course of the monitoring period.
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