Article (Scientific journals)
COSMOGRAIL XIX: Time delays in 18 strongly lensed quasars from 15 years of optical monitoring
Millon, M.; Courbin, F.; Bonvin, V. et al.
2020In Astronomy and Astrophysics, 640, p. 105
Peer Reviewed verified by ORBi
 

Files


Full Text
2020_AA_640_A105_Millon_et_al.pdf
Publisher postprint (14.5 MB)
Originally published in A&A
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
astro-ph.CO; COSMOGRAIL; time-delay; strong-lensing; monitoring
Abstract :
[en] We present the results of 15 years of monitoring of lensed quasars conducted by the COSMOGRAIL program at the Leonhard Euler 1.2m Swiss Telescope. The decade-long light curves of 23 lensed QSOs are presented for the first time. We complement our data set with other monitoring data available in the literature to measure the time delays in 18 systems, among which 9 reach a relative precision better than 15% for at least one time delay. To achieve this, we develop an automated version of the curve-shifting toolbox PyCS to ensure robust estimation of the time delay in the presence of microlensing while accounting for the errors due to imperfect representation of microlensing. We also reanalyze the previously published time delays of RX J1131$-$1231 and HE 0435$-$1223, adding respectively 6 and 2 new seasons of monitoring and confirming the previous time-delay measurements. When the time delay measurement is possible, we correct the light curves of the lensed images from their time delay and present the difference curves to highlight the microlensing signal contained in the data. This is to date the largest sample of decade-long lens monitoring data, useful to measure $H_0$, to measure the size of quasar accretion disks with microlensing, and to study quasar variability.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Millon, M.
Courbin, F.
Bonvin, V.
Paic, E.
Meylan, G.
Tewes, M.
Sluse, Dominique  ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Magain, Pierre  ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Chan, J. H. H.
Galan, A.
Joseph, R.
Lemon, C.
Tihhonova, O.
Anderson, R. I.
Marmier, M.
Chazelas, B.
Lendl, M.
Triaud, A. H. M. J.
Wyttenbach, A.
More authors (9 more) Less
Language :
English
Title :
COSMOGRAIL XIX: Time delays in 18 strongly lensed quasars from 15 years of optical monitoring
Publication date :
August 2020
Journal title :
Astronomy and Astrophysics
ISSN :
0004-6361
eISSN :
1432-0746
Publisher :
EDP Sciences, Les Ulis, France
Volume :
640
Pages :
A105
Peer reviewed :
Peer Reviewed verified by ORBi
European Projects :
H2020 - 787886 - COSMICLENS - Cosmology with Strong Gravitational Lensing
Funders :
CE - Commission Européenne [BE]
Available on ORBi :
since 23 August 2020

Statistics


Number of views
70 (7 by ULiège)
Number of downloads
31 (2 by ULiège)

Scopus citations®
 
46
Scopus citations®
without self-citations
34
OpenCitations
 
26

Bibliography


Similar publications



Contact ORBi