Browsing by Author "Sluse, D."

Now showing 1 - 6 of 6
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    COSMOGRAIL : the COSmological MOnitoring of GRAvItational Lenses.
    (2006) Saha, P.; Courbin, F.; Sluse, D.; Dye, S.; Meylan, G.
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    COSMOGRAIL XVIII. time delays of the quadruply lensed quasar WFI2033-4723
    (2019) Bonvin, V.; Millon, M.; Chan, J. H. -H.; Courbin, F.; Rusu, C. E.; Sluse, D.; Suyu, S. H.; Wong, K. C.; Fassnacht, C. D.; Marshall, P. J.; Treu, T.; Buckley-Geer, E.; Frieman, J.; Hempel, A.; Kim, S.; Lachaume, R.; Rabus, M.; Chao, D. C. -Y.; Chijani, M.; Gilman, D.; Gilmore, K.; Rojas, K.; Williams, P.; Anguita, T.; Kochanek, C. S.; Morgan, C.; Motta, V.; Tewes, M.; Meylan, G.
    We present new measurements of the time delays of WFI2033-4723. The data sets used in this work include 14 years of data taken at the 1.2 m Leonhard Euler Swiss telescope, 13 years of data from the SMARTS 1.3 m telescope at Las Campanas Observatory and a single year of high-cadence and high-precision monitoring at the MPIA 2.2 m telescope. The time delays measured from these different data sets, all taken in the R-band, are in good agreement with each other and with previous measurements from the literature. Combining all the time-delay estimates from our data sets results in Delta t(AB) = 36.2(-0.8)(+0.7) days (2.1% precision), Delta t(AC) = 23.3(-1.4)(+1.2) days (5.6%) and Delta t(BC) = 59.4(-1.3)(+1.3) days (2.2%). In addition, the close image pair A1-A2 of the lensed quasars can be resolved in the MPIA 2.2 m data. We measure a time delay consistent with zero in this pair of images. We also explore the prior distributions of microlensing time-delay potentially affecting the cosmological time-delay measurements of WFI2033-4723. Our time-delay measurements are not precise enough to conclude that microlensing time delay is present or absent from the data. This work is part of a H0LiCOW series focusing on measuring the Hubble constant from WFI2033-4723.
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    Microlensing of the broad-line region in the quadruply imaged quasar HE0435-1223
    (2014) Braibant, L.; Hutsemekers, D.; Sluse, D.; Anguita, T.; Garcia-Vergara, C. J.
    Using infrared spectra of the z = 1.693 quadruply lensed quasar HE0435-1223 acquired in 2009 with the spectrograph SINFONI at the ESO Very Large Telescope, we have detected a clear microlensing effect in images A and D. While microlensing affects the blue and red wings of the H alpha line profile in image D very differently, it de-magnifies the line core in image A. The combination of these different effects sets constraints on the line-emitting region; these constraints suggest that a rotating ring is at the origin of the H alpha line. Visible spectra obtained in 2004 and 2012 indicate that the MgII line profile is microlensed in the same way as the H alpha line. Our results therefore favour flattened geometries for the low-ionization line-emitting region, for example, a Keplerian disk. Biconical models cannot be ruled out but require more fine-tuning. Flux ratios between the different images are also derived and confirm flux anomalies with respect to estimates from lens models with smooth mass distributions.
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    TDCOSMO II. Six new time delays in lensed quasars from high-cadence monitoring at the MPIA 2.2m telescope
    (2020) Millon, M.; Courbin, F.; Bonvin, V.; Buckley Geer, E.; Fassnacht, C. D.; Frieman, J.; Marshall, P. J.; Kim, Seoung Ha; Lachaume, Regis; Rabus, Markus; Suyu, S. H.; Treu, T.; Anguita, T.; Motta, V.; Agnello, A.; Chan, J. H. H.; Chao, D. C. Y.; Chijani, M.; Gilman, D.; Gilmore, K.; Lemon, C.; Lucey, J. R.; Melo, A.; Paic, E.; Rojas, K.; Sluse, D.; Williams, P. R.; Hempel, A.; Rabus, Markus
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