MiNDSTEp differential photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756: microlensing and a new time delay
Research output: Contribution to journal › Journal article › peer-review
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.
Based on data collected by MiNDSTEp with the Danish 1.54 m telescope at
the ESO La Silla observatory.
Original language | English |
---|---|
Article number | A49 |
Journal | Astronomy & Astrophysics |
Volume | 597 |
ISSN | 0004-6361 |
DOIs | |
Publication status | Published - 2017 |
- gravitational lensing: micro, techniques: photometric, quasars: general
Research areas
Links
- http://arxiv.org/pdf/1610.03732
Submitted manuscript
ID: 170453734