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arXiv · 0903.1027

Results of optical monitoring of 5 SDSS double QSOs with the Nordic Optical Telescope

Danuta Paraficz·Jens Hjorth·Árdís Elíasdóttir
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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 116 days, which, for a Singular Isothermal Ellipsoid model, corresponds to a Hubble constant of 73 km/s/Mpc. Simultaneous pixeleted modeling of five other systems for which a time delay has now been previously measured at the NOT leads to H_0 = 61.5 km/s/Mpc. Finally, by comparing lightcurves of the two images of each system, suitably shifted by the predicted or observed time-delays, we found no evidence for microlensing variability over the course of the monitoring period.

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Danuta Paraficz, Jens Hjorth, Árdís Elíasdóttir. 2009-03-05. Results of optical monitoring of 5 SDSS double QSOs with the Nordic Optical Telescope. https://doi.org/10.1051/0004-6361%2F200811387

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