Abstract We present the lens mass model of the quadruplyimaged gravitationally lensed quasar WFI2033−4723, and perform a blind cosmographical analysis based on this system. Our analysis combines (1) timedelay measurements from 14 years of data obtained by the COSmological MOnitoring of GRAvItational Lenses (COSMOGRAIL) collaboration, (2) highresolution Hubble Space Telescope imaging, (3) a measurement of the velocity dispersion of the lens galaxy based on ESOMUSE data, and (4) multiband, widefield imaging and spectroscopy characterizing the lens environment. We account for all known sources of systematics, including the influence of nearby perturbers and complex lineofsight structure, as well as the parametrization of the light and mass profiles of the lensing galaxy. After unblinding, we determine the effective timedelay distance to be $4784_{248}^{+399}~\mathrm{Mpc}$, an average precision of $6.6{{\ \rm per\ cent}}$. This translates to a Hubble constant $H_{0} = 71.6_{4.9}^{+3.8}~\mathrm{km~s^{1}~Mpc^{1}}$, assuming a flat ΛCDM cosmology with a uniform prior on Ωm in the range [0.05, 0.5]. This work is part of the H0 Lenses in COSMOGRAIL’s Wellspring (H0LiCOW) collaboration, and the full timedelay cosmography results from a total of six strongly lensed systems are presented in a companion paper (H0LiCOW XIII).
STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408−5354
ABSTRACT We present a blind timedelay cosmographic analysis for the lens system DES J0408−5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cost of increased modelling complexity with respect to previously analysed systems. We perform detailed modelling of the mass distribution for this lens system using three band Hubble Space Telescope imaging. We combine the measured time delays, lineofsight central velocity dispersion of the deflector, and statistically constrained external convergence with our lens models to estimate two cosmological distances. We measure the ‘effective’ timedelay distance corresponding to the redshifts of the deflector and the lensed quasar $D_{\Delta t}^{\rm eff}=$$3382_{115}^{+146}$ Mpc and the angular diameter distance to the deflector Dd = $1711_{280}^{+376}$ Mpc, with covariance between the two distances. From these constraints on the cosmological distances, we infer the Hubble constant H0= $74.2_{3.0}^{+2.7}$ km s−1 Mpc−1 assuming a flat ΛCDM cosmology and a uniform prior for Ωm as $\Omega _{\rm m} \sim \mathcal {U}(0.05, 0.5)$. This measurement gives the most precise constraint on H0 to date from a single lens. Our measurement is consistent with that obtained from the previous sample of six lenses analysed by the H0 more »
 Authors:
 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
 Publication Date:
 NSFPAR ID:
 10175665
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Volume:
 494
 Issue:
 4
 Page Range or eLocationID:
 6072 to 6102
 ISSN:
 00358711
 Sponsoring Org:
 National Science Foundation
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