2019MNRAS.490.1743C

We present the measurement of the Hubble constant, H₀, with three strong gravitational lens systems. We describe a blind analysis of both PG 1115+080 and HE 0435-1223 as well as an extension of our previous analysis of RXJ 1131-1231. For each lens, we combine new adaptive optics (AO) imaging from the Keck Telescope, obtained as part of the SHARP (Strong-lensing High Angular Resolution Programme) AO effort, with Hubble Space Telescope (HST) imaging, velocity dispersion measurements, and a description of the line-of-sight mass distribution to build an accurate and precise lens mass model. This mass model is then combined with the COSMOGRAIL-measured time delays in these systems to determine H₀. We do both an AO-only and an AO + HST analysis of the systems and find that AO and HST results are consistent. After unblinding, the AO-only analysis gives H₀=82.8^+9.4_–8.3∼ km s^–1 Mpc^–1 for PG 1115+080, H₀=70.1^+5.3_–4.5∼ km s^–1 Mpc^–1 for HE 0435-1223, and H₀=77.0^+4.0_–4.6∼ km s^–1 Mpc^–1 for RXJ 1131-1231. The joint AO-only result for the three lenses is H₀=75.6^+3.2_–3.3∼ km s^–1 Mpc^–1. The joint result of the AO + HST analysis for the three lenses is H₀=76.8^+2.6_–2.6∼ km s^–1 Mpc^–1. All of these results assume a flat Λ cold dark matter cosmology with a uniform prior on Ω_m in [0.05, 0.5] and H₀ in [0, 150] km s^–1 Mpc^–1. This work is a collaboration of the SHARP and H0LiCOW teams, and shows that AO data can be used as the high-resolution imaging component in lens-based measurements of H₀. The full time-delay cosmography results from a total of six strongly lensed systems are presented in a companion paper.