collaborators

5 papers

astro-ph.CO2026

Investigating the Dark Energy Constraint from Strongly Lensed AGN at LSST-Scale

Sydney Erickson, Martin Millon, Padmavathi Venkatraman +12

The paper presents a scalable hierarchical inference framework to jointly analyze hundreds of strongly lensed AGN time delays from LSST, forecasting a ~2.5% measurement of H0 and a…

astro-ph.GA2026

TDCOSMO. XXIII. Measurement of the Hubble constant from the doubly lensed quasar HE1104-1805

Eric Paic, Frédéric Courbin, Christopher D. Fassnacht +18

Time-delay cosmography leverages strongly lensed quasars to measure the Universe's current expansion rate, H_0, independently from other methods. While the latest TDCOSMO results r…

astro-ph.CO2025

TDCOSMO 2025: Cosmological constraints from strong lensing time delays

TDCOSMO Collaboration, Simon Birrer, Elizabeth J. Buckley-Geer +30

We present cosmological constraints from 8 strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar…

astro-ph.GA2025

TDCOSMO XXII: Triaxiality and projection effects in time-delay cosmography

Xiang-Yu Huang, Simon Birrer, Michele Cappellari +3

Constraining the mass-sheet degeneracy (MSD) is crucial for improving the precision and accuracy of time-delay cosmography. Joint analyses of lensing and stellar kinematics are wid…

astro-ph.CO2025

Lens Model Accuracy in the Expected LSST Lensed AGN Sample

Padmavathi Venkatraman, Sydney Erickson, Phil Marshall +13

Strong gravitational lensing of active galactic nuclei (AGN) enables measurements of cosmological parameters through time-delay cosmography (TDC). With data from the upcoming LSST…