3 papers
astro-ph.CO2026
HST imaging, pipeline modeling, and time-delay predictions of 2 triply-imaged and 15 quadruply-imaged lensed quasars
William Sheu, Tommaso Treu, Adriano Agnello +10
The Hubble-Lema\^ıtre tension remains a significant challenge in modern cosmology, exhibiting a discrepancy between early-Universe cosmic microwave background measurements and loca…
astro-ph.CO2025
TDCOSMO XVII. New time delays in 22 lensed quasars from optical monitoring with the ESO-VST 2.6m and MPG 2.2m telescopes
Frédéric Dux, Martin Millon, Aymeric Galan +29
We present new time delays, the main ingredient of time delay cosmography, for 22 lensed quasars resulting from high-cadence r-band monitoring on the 2.6 m ESO VLT Survey Telescope…
astro-ph.CO2024
J1721+8842: The first Einstein zig-zag lens
F. Dux, M. Millon, C. Lemon +16
We report the discovery of the first example of an Einstein zig-zag lens, an extremely rare lensing configuration. In this system, J1721+8842, six images of the same background qua…