A SHARP view of H0LiCOW: H0 from three time-delay gravitational lens systems with adaptive optics imaging

Abstract

We present the measurement of the Hubble Constant, H 0 , 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 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 H 0 . 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 H 0 = 82.8 +9.4 −8.3 km s −1 Mpc −1 for PG 1115+080, H 0 = 70.1 +5.3 −4.5 km s −1 Mpc −1 for HE 0435−1223, and H 0 = 77.0 +4.0 −4.6 km s −1 Mpc −1 for RXJ 1131−1231. The joint AOonly result for the three lenses is H 0 = 75.6 +3.2 −3.3 km s −1 Mpc −1 . The joint result of the AO+HST analysis for the three lenses is H 0 = 76.8 +2.6−2.6 km s −1 Mpc −1 . All of the above results assume a flat Λ cold dark matter cosmology with a uniform prior on Ω m in [0.05, 0.5] and H 0 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 H 0 . The full time-delay cosmography results from a total of six strongly lensed systems are presented in a companion paper.

SHARP – VI. Evidence for CO (1–0) molecular gas extended on kpc-scales in AGN star-forming galaxies at high redshift

“…MG J0751+2716 and JVAS B1938+666 were observed at 2.12 μm (K band) with the adaptive-optics system on the W. M. Keck-II Telescope as part of the Strong-lensing at High Angular Resolution Programme (SHARP;McKean et al 2007;Lagattuta, Auger & Fassnacht 2010;Lagattuta et al 2012;Vegetti et al 2012;Hsueh et al 2016Hsueh et al , 2017Chen et al 2016;Spingola et al 2018;Chen et al 2019;Hsueh et al 2020). The targets were observed using the NIRC2 instrument (narrow camera), which provides a field of view of 10 arcsec × 10 arcsec, and a pixel scale of 9.942 mas pixel −1 .…”

A CMB search for the neutrino mass mechanism and its relation to the Hubble tension

“…Thus, quite remarkably, the CMB is providing an indirect probe of the neutrino mass mechanism at collider energy scales (albeit unaccessible to colliders due to their small couplings), but using feeble interactions with neutrinos in the early Universe. While the ΛCDM model has been incredibly successful at describing both high-and low-redshift cosmological observations, a concerning tension has recently emerged between the value of the Hubble constant H 0 inferred from the CMB using observations by Planck [34], and various local measurements performed using observations of type-Ia supernovae 1 (with distances calibrated using measurements of cepheids [41,42]) 2 , and strongly lensed quasars [43][44][45][46] 3 . Depending both on the choice of distance calibration and how one chooses to combine datasets, the outstanding tension is determined to be at the level of ∼ 4 − 6 σ [38,47].…”

Localizing merging black holes with sub-arcsecond precision using gravitational-wave lensing

“…These uncertainties are significantly broader than the errors achieved for detailed models of lenses with highresolution imaging (e.g. Birrer et al 2019;Chen et al 2019). The errors also do not include the correlations between parameters whose inclusion would improve our discriminatory power and are thus conservative.…”