MiNDSTEp differential photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756 : microlensing and a new time delay
Abstract
Aims: We present V and R photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756. The data were taken by the MiNDSTEp collaboration with the 1.54 m Danish telescope at the ESO La Silla observatory from 2008 to 2012. Methods: Differential photometry has been carried out using the image subtraction method as implemented in the HOTPAnTS package, additionally using GALFIT for quasar photometry. Results: The quasar WFI 2033-4723 showed brightness variations of order 0.5 mag in V and R during the campaign.The two lensed components of quasar HE 0047-1756 varied by 0.2-0.3 mag within five years. We provide, for the first time, an estimate of the time delay of component B with respect to A of Δt = (7.6±1.8) days for this object. We also find evidence for a secular evolution of the magnitude difference between components A and B in both filters,which we explain as due to a long-duration microlensing event. Finally we find that both quasars WFI 2033-4723 and HE 0047-1756 become bluer when brighter, which is consistent with previous studies.
Citation
Giannini , E , Schmidt , R W , Wambsganss , J , Alsubai , K , Andersen , J M , Anguita , T , Bozza , V , Bramich , D M , Browne , P , Calchi Novati , S , Damerdji , Y , Diehl , C , Dodds , P , Dominik , M , Elyiv , A , Fang , X , Figuera Jaimes , R , Finet , F , Gerner , T , Gu , S , Hardis , S , Harpsøe , K , Hinse , T C , Hornstrup , A , Hundertmark , M , Jessen-Hansen , J , Jørgensen , U G , Juncher , D , Kains , N , Kerins , E , Korhonen , H , Liebig , C , Lund , M N , Lundkvist , M S , Maier , G , Mancini , L , Masi , G , Mathiasen , M , Penny , M , Proft , S , Rabus , M , Rahvar , S , Ricci , D , Scarpetta , G , Sahu , K , Schäfer , S , Schönebeck , F , Skottfelt , J , Snodgrass , C , Southworth , J , Surdej , J , Tregloan-Reed , J , Vilela , C , Wertz , O & Zimmer , F 2017 , ' MiNDSTEp differential photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756 : microlensing and a new time delay ' , Astronomy & Astrophysics , vol. 597 , A49 . https://doi.org/10.1051/0004-6361/201527422
Publication
Astronomy & Astrophysics
Status
Peer reviewed
ISSN
0004-6361Type
Journal article
Description
MAS. M.D. and M.H. are supported by NPRP grant NPRP-09-476-1-78 from the Qatar National Research Fund (a member of Qatar Foundation).Collections
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