<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305"^^ . "This work focusses on studying the brightness variation of gravitationally lensed\r\nmultiply imaged quasars. The main goal is the optimization of the relative differential\r\nphotometry procedures, which are based on the difference image analysis (DIA)\r\nmethod. Moreover, it aims at isolating uncorrelated flux variations among the quasar\r\nimages, which can be explained as due to quasar microlensing events, and at the estimation\r\nof the time delays of the observed systems from the retrieved light curves.\r\nWe present V and R photometry of the gravitationally lensed quasars WFI 2033-4723,\r\nHE 0047-1756 and Q2237+0305. The analyzed data belong to the MiNDSTEp collaboration\r\nand were taken with the 1.54m Danish telescope at ESO/La Silla from 2008 to\r\n2012. The differential photometry is based on the already published method by Alard &\r\nLupton as implemented in the HOTPAnTS package, and additionally uses the GALFIT\r\npackage for obtaining the quasar photometry.\r\nThe quasar WFI 2033-4723 shows brightness variations of ~ 0.5 mag in V and R during\r\nthe campaign. The two lensed components of quasar HE 0047-1756 vary by ~\r\n0.2 to 0.3 mag within five years. We provide for the first time an estimate of the time\r\ndelay of component B with respect to A of Δt = (7.6+-1.8) days for this object. We also\r\nfind evidence for a secular evolution of the magnitude difference between components\r\nA and B in both filters, which we explain as due to a long-duration microlensing event.\r\nWe also find that both quasars WFI 2033-4723 and HE 0047-1756 become bluer when\r\nbrighter, which is consistent with previous studies. The quasar Q2237+0305 shows impressive\r\nuncorrelated variations of the four components in both the V and R bands, with\r\nbrightness variations between ~0.2 and ~1.3 mag. In particular, component D shows\r\nflux variations of ~ 1.3 mag in the V band and ~0.8 mag in the R band during the 5-year\r\nmonitoring campaign, along a caustic-crossing feature of the light curve. We also find\r\nthat the color of this component becomes redder by ~0.6 mag while it becomes fainter.\r\nImage C becomes brighter by ~0.7 mag between the last two monitoring seasons and\r\nthis again suggests a high-magnification microlensing event."^^ . "2017" . . . . . . . "Emanuela"^^ . "Giannini"^^ . "Emanuela Giannini"^^ . . . . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (PDF)"^^ . . . "Emanuela_Giannini.pdf"^^ . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (Other)"^^ . . . . . . "preview.jpg"^^ . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (Other)"^^ . . . . . . "medium.jpg"^^ . . . "MiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305 (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #22683 \n\nMiNDSTEp differential photometry of the gravitationally lensed quasars WFI2033-4723, HE0047-1756 and Q2237+0305\n\n" . "text/html" . .