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COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses IV. Models of prospective time-delay lenses

P. Saha·F. Courbin·D. Sluse·S. Dye·G. Meylan
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Abstract

Aims: To predict time delays for a sample of gravitationally lensed quasars and to evaluate the accuracy that can be realistically achieved on the value of H_0. Methods: We consider 14 lensed quasars that are candidates for time-delay monitoring and model them in detail using pixelized lens models. For each system, we provide a mass map, arrival-time surface and the distribution of predicted time-delays in a concordance cosmology, assuming H_0^{-1}=14 Gyr (H_0=70 in local units). Based on the predicted time-delays and on the observational circumstances, we rate each lens as `excellent' or `good' or `unpromising' for time-delay monitoring. Finally, we analyze simulated time delays for the 11 lens rated excellent or good, and show that H_0 can be recovered to a precision of 5%. Results: In combination with COSMOGRAIL paper I on the temporal sampling of lensed quasar light curves, the present work will help design monitoring campaigns of lensed quasars.

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P. Saha, F. Courbin, D. Sluse, S. Dye, G. Meylan. 2006-01-17. COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses IV. Models of prospective time-delay lenses. https://doi.org/10.1051/0004-6361%3A20052929

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