TDCOSMO: II. Six new time delays in lensed quasars from high-cadence monitoring at the MPIA 2.2 m telescope

Millon, M.; Courbin, F.; Bonvin, V.; Buckley-Geer, E.; Fassnacht, C.D.; Frieman, J.; Marshall, P.J.; Suyu, S.H.; Treu, T.; Anguita, T.; Motta, V.; Agnello, A.; Chan, J.H.H.; Chao, D.C.-Y.; Chijani, M.; Gilman, D.; Gilmore, K.; Lemon, C.; Lucey, J.R.; Melo, A.; Paic, E.; Rojas, K.; Sluse, D.; Williams, P.R.; Hempel, A.; Kim, S.; Lachaume, R.; Rabus, M.

Abstract

We present six new time-delay measurements obtained from Rc-band monitoring data acquired at the Max Planck Institute for Astrophysics (MPIA) 2.2 m telescope at La Silla observatory between October 2016 and February 2020. The lensed quasars HE 0047−1756, WG 0214−2105, DES 0407−5006, 2M 1134−2103, PSJ 1606−2333, and DES 2325−5229 were observed almost daily at high signal-to-noise ratio to obtain highquality light curves where we can record fast and small-amplitude variations of the quasars. We measured time delays between all pairs of multiple images with only one or two seasons of monitoring with the exception of the time delays relative to image D of PSJ 1606−2333. The most precise estimate was obtained for the delay between image A and image B of DES 0407−5006, where τAB = −128.4 +3.5 −3.8 d (2.8% precision) including systematics due to extrinsic variability in the light curves. For HE 0047−1756, we combined our high-cadence data with measurements from decade-long light curves from previous COSMOGRAIL campaigns, and reach a precision of 0.9 d on the final measurement. The present work demonstrates the feasibility of measuring time delays in lensed quasars in only one or two seasons, provided high signal-to-noise ratio data are obtained at a cadence close to daily.

Citation

Millon, M., Courbin, F., Bonvin, V., Buckley-Geer, E., Fassnacht, C., Frieman, J., Marshall, P., Suyu, S., Treu, T., Anguita, T., Motta, V., Agnello, A., Chan, J., Chao, D.-Y., Chijani, M., Gilman, D., Gilmore, K., Lemon, C., Lucey, J., Melo, A., …Rabus, M. (2020). TDCOSMO: II. Six new time delays in lensed quasars from high-cadence monitoring at the MPIA 2.2 m telescope. Astronomy & Astrophysics, 642, Article A193. https://doi.org/10.1051/0004-6361/202038698

• Journal Article Type: Article
• Acceptance Date: Aug 21, 2020
• Online Publication Date: Oct 20, 2020
• Publication Date: 2020-10
• Deposit Date: Nov 11, 2020
• Publicly Available Date: Nov 11, 2020
• Journal: Astronomy and astrophysics.
• Print ISSN: 0004-6361
• Electronic ISSN: 1432-0746
• Publisher: EDP Sciences
• Peer Reviewed: Peer Reviewed
• Volume: 642
• Article Number: A193
• DOI: https://doi.org/10.1051/0004-6361/202038698
• Public URL: https://durham-repository.worktribe.com/output/1257382