Search Publications
Lyman-alpha forests cool warm dark matter
Palanque-Delabrouille, Nathalie; Viel, Matteo; Yèche, Christophe +2 more
The free-streaming of keV-scale particles impacts structure growth on scales that are probed by the Lyman-alpha forest of distant quasars. Using an unprecedentedly large sample of medium-resolution QSO spectra from the ninth data release of SDSS, along with a state-of-the-art set of hydrodynamical simulations to model the Lyman-alpha forest in the…
Hubble Imaging of the Ionizing Radiation from a Star-forming Galaxy at Z=3.2 with fesc>50%
Giavalisco, M.; Castellano, M.; Pentericci, L. +20 more
Star-forming galaxies are considered to be the leading candidate sources dominating cosmic reionization at z\gt 7: the search for analogs at moderate redshift showing Lyman continuum (LyC) leakage is currently an active line of research. We have observed a star-forming galaxy at z = 3.2 with Hubble/WFC3 in the F336W filter, corresponding to the 73…
The habitability of Proxima Centauri b. I. Irradiation, rotation and volatile inventory from formation to the present
Guinan, Edward F.; Engle, Scott G.; Reiners, Ansgar +9 more
Proxima b is a planet with a minimum mass of 1.3M⊕ orbiting within the habitable zone (HZ) of Proxima Centauri, a very low-mass, active star and the Sun's closest neighbor. Here we investigate a number of factors related to the potential habitability of Proxima b and its ability to maintain liquid water on its surface. We set the stage …
An HST/COS Survey of the Low-redshift Intergalactic Medium. I. Survey, Methodology, and Overall Results
Savage, Blair D.; Shull, J. Michael; Danforth, Charles W. +12 more
We use high-quality, medium-resolution Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) observations of 82 UV-bright active galactic nuclei (AGNs) at redshifts zAGN < 0.85 to construct the largest survey of the low-redshift intergalactic medium (IGM) to date: 5138 individual extragalactic absorption lines in H I and 25 di…
Evolution of water production of 67P/Churyumov-Gerasimenko: An empirical model and a multi-instrument study
Altwegg, K.; Huang, Z.; Nilsson, H. +24 more
We examine the evolution of the water production of comet 67P/Churyumov-Gerasimenko during the Rosetta mission (2014 June-2016 May) based on in situ and remote sensing measurements made by Rosetta instruments, Earth-based telescopes and through the development of an empirical coma model. The derivation of the empirical model is described and the m…
An extreme [O III] emitter at z = 3.2: a low metallicity Lyman continuum source
Giavalisco, M.; Castellano, M.; Pentericci, L. +16 more
Aims: Cosmic reionization is an important process occurring in the early epochs of the Universe. However, because of observational limitations due to the opacity of the intergalactic medium to Lyman continuum photons, the nature of ionizing sources is still not well constrained. While high-redshift star-forming galaxies are thought to be the …
Detection of H2O and Evidence for TiO/VO in an Ultra-hot Exoplanet Atmosphere
Nikolov, Nikolay; Drummond, Benjamin; Gibson, Neale P. +7 more
We present a primary transit observation for the ultra-hot (T eq ∼ 2400 K) gas giant expolanet WASP-121b, made using the Hubble Space Telescope Wide Field Camera 3 in spectroscopic mode across the 1.12-1.64 µm wavelength range. The 1.4 µm water absorption band is detected at high confidence (5.4σ) in the planetary atmosphere…
Bimodality of low-redshift circumgalactic O VI in non-equilibrium EAGLE zoom simulations
Tumlinson, Jason; Crain, Robert A.; Schaye, Joop +7 more
We introduce a series of 20 cosmological hydrodynamical simulations of L* (M200 = 1011.7-1012.3 M⊙) and group-sized (M200 = 1012.7-1013.3 M⊙) haloes run with the model used for the EAGLE project, which additionally includes a non-equilibrium ionization and cool…
The Link between Turbulence, Magnetic Fields, Filaments, and Star Formation in the Central Molecular Zone Cloud G0.253+0.016
Testi, L.; Federrath, C.; Bally, J. +8 more
Star formation is primarily controlled by the interplay between gravity, turbulence, and magnetic fields. However, the turbulence and magnetic fields in molecular clouds near the Galactic center may differ substantially compared to spiral-arm clouds. Here we determine the physical parameters of the central molecular zone (CMZ) cloud G0.253+0.016, …
Precise Strong Lensing Mass Modeling of Four Hubble Frontier Field Clusters and a Sample of Magnified High-redshift Galaxies
Ouchi, Masami; Shimasaku, Kazuhiro; Oguri, Masamune +2 more
We conduct precise strong lensing mass modeling of four Hubble Frontier Field (HFF) clusters, Abell 2744, MACS J0416.1-2403, MACS J0717.5+3745, and MACS J1149.6+2223, for which HFF imaging observations are completed. We construct a refined sample of more than 100 multiple images for each cluster by taking advantage of the full-depth HFF images, an…