Courbin, F;
Bonvin, V;
Buckley-Geer, E;
Fassnacht, CD;
Frieman, J;
Lin, H;
Marshall, PJ;
... Wester, W; + view all
(2018)
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XVI. Time delays for the quadruply imaged quasar DES J0408-5354 with high-cadence photometric monitoring.
Astronomy & Astrophysics
, 609
, Article A71. 10.1051/0004-6361/201731461.
Preview |
Text
aa31461-17.pdf - Published Version Download (1MB) | Preview |
Abstract
We present time-delay measurements for the new quadruple imaged quasar DES J0408−5354, the first quadruple imaged quasar found in the Dark Energy Survey (DES). Our result is made possible by implementing a new observational strategy using almost daily observations with the MPIA 2.2 m telescope at La Silla observatory and deep exposures reaching a signal-to-noise ratio of about 1000 per quasar image. This data qualityallows us to catch small photometric variations (a few mmag rms) of the quasar, acting on temporal scales much shorter than microlensing, and hence making the time delay measurement very robust against microlensing. In only seven months we very accurately measured one of the time delays in DES J0408−5354: Δt(AB) = −112.1 ± 2.1 days (1.8%) using only the MPIA 2.2 m data. In combination with data taken with the 1.2 m Euler Swiss telescope, we also measured two delays involving the D component of the system Δt(AD) = −155.5 ± 12.8 days (8.2%) and Δt(BD) = −42.4 ± 17.6 days (41%), where all the error bars include systematics. Turning these time delays into cosmological constraints will require deep Hubble Space Telescope (HST) imaging or ground-based adaptive optics (AO), and information on the velocity field of the lensing galaxy.
| Type: | Article |
|---|---|
| Title: | COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XVI. Time delays for the quadruply imaged quasar DES J0408-5354 with high-cadence photometric monitoring |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1051/0004-6361/201731461 |
| Publisher version: | https://doi.org/10.1051/0004-6361/201731461 |
| Language: | English |
| Additional information: | This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | Science & Technology, Physical Sciences, Astronomy & Astrophysics, methods: data analysis, gravitational lensing: strong, cosmological parameters, HUBBLE CONSTANT, HE 0435-1223, PRECISION, DECONVOLUTION, DISCOVERY, MODELS, SAMPLE, SIGHT, H-0 |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10042312 |
Archive Staff Only
 |
View Item |
