Search Publications
H0LiCOW - V. New COSMOGRAIL time delays of HE 0435-1223: H0 to 3.8 per cent precision from strong lensing in a flat ΛCDM model
Treu, T.; Auger, M. W.; Koopmans, L. V. E. +15 more
We present a new measurement of the Hubble Constant H0 and other cosmological parameters based on the joint analysis of three multiply imaged quasar systems with measured gravitational time delays. First, we measure the time delay of HE 0435-1223 from 13-yr light curves obtained as part of the COSMOGRAIL project. Companion papers detail…
The Hubble Space Telescope UV Legacy Survey of Galactic globular clusters - IX. The Atlas of multiple stellar populations
Salaris, M.; Anderson, J.; Milone, A. P. +17 more
We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic GCs', to identify and characterize their multiple stellar populations. For each cluster the pseudo-two-colour diagram (or `chromosome map') is presented, built with a su…
A deep ALMA image of the Hubble Ultra Deep Field
Ivison, R. J.; Scott, D.; van Kampen, E. +36 more
We present the results of the first, deep Atacama Large Millimeter Array (ALMA) imaging covering the full ≃4.5 arcmin2 of the Hubble Ultra Deep Field (HUDF) imaged with Wide Field Camera 3/IR on HST. Using a 45-pointing mosaic, we have obtained a homogeneous 1.3-mm image reaching σ1.3 ≃ 35 µJy, at a resolution of ≃0.7 a…
Lyα and C III] emission in z = 7-9 Galaxies: accelerated reionization around luminous star-forming systems?
Charlot, Stéphane; Chevallard, Jacopo; Tang, Mengtao +9 more
We discuss new Keck/MOSFIRE spectroscopic observations of four luminous galaxies at z ≃ 7-9 selected to have intense optical line emission by Roberts-Borsani et al. Previous follow-up has revealed Lyα in two of the four galaxies. Our new MOSFIRE observations confirm that Lyα is present in the entire sample. We detect Lyα emission in the galaxy COS…
The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: anisotropic galaxy clustering in Fourier space
Ross, Nicholas P.; Schneider, Donald P.; Eisenstein, Daniel J. +20 more
We investigate the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 sample, which consists of 1198 006 galaxies in the redshift range 0.2 < z < 0.75 and a sky coverage of 10 252 deg2. We analyse this data set in Fourier space, using the power-spectrum multipoles to measure redshift-space…
Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13
Salvaterra, R.; Haberl, F.; Greiner, J. +11 more
NGC 7793 P13 is a variable (luminosity range ∼100) ultraluminous X-ray source proposed to host a stellar-mass black hole of less than 15 M⊙ in a binary system with orbital period of 64 d and a 18-23 M⊙ B9Ia companion. Within the EXTraS (Exploring the X-ray Transient and variable Sky) project, we discovered pulsations at a per…
H0LiCOW - I. H0 Lenses in COSMOGRAIL's Wellspring: program overview
Treu, T.; Blandford, R. D.; Auger, M. W. +21 more
Strong gravitational lens systems with time delays between the multiple images allow measurements of time-delay distances, which are primarily sensitive to the Hubble constant that is key to probing dark energy, neutrino physics and the spatial curvature of the Universe, as well as discovering new physics. We present H0LiCOW (H0 Lenses …
CFHTLenS revisited: assessing concordance with Planck including astrophysical systematics
Heymans, Catherine; van Waerbeke, Ludovic; Choi, Ami +9 more
We investigate the impact of astrophysical systematics on cosmic shear cosmological parameter constraints from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) and the concordance with cosmic microwave background measurements by Planck. We present updated CFHTLenS cosmic shear tomography measurements extended to degree scales using a c…
The Frontier Fields lens modelling comparison project
Sharon, K.; Diego, J. M.; Zitrin, A. +20 more
Gravitational lensing by clusters of galaxies offers a powerful probe of their structure and mass distribution. Several research groups have developed techniques independently to achieve this goal. While these methods have all provided remarkably high-precision mass maps, particularly with exquisite imaging data from the Hubble Space Telescope (HS…
Growing supermassive black holes in the late stages of galaxy mergers are heavily obscured
Sanders, D. B.; Harrison, F.; Stern, D. +10 more
Mergers of galaxies are thought to cause significant gas inflows to the inner parsecs, which can activate rapid accretion on to supermassive black holes (SMBHs), giving rise to active galactic nuclei (AGN). During a significant fraction of this process, SMBHs are predicted to be enshrouded by gas and dust. Studying 52 galactic nuclei in infrared-s…