Search Publications
An Older, More Quiescent Universe from Panchromatic SED Fitting of the 3D-HST Survey
Franx, Marijn; van Dokkum, Pieter; Conroy, Charlie +8 more
Galaxy observations are influenced by many physical parameters: stellar masses, star formation rates (SFRs), star formation histories (SFHs), metallicities, dust, black hole activity, and more. As a result, inferring accurate physical parameters requires high-dimensional models that capture or marginalize over this complexity. Here we reassess inf…
Inferences on the timeline of reionization at z ∼ 8 from the KMOS Lens-Amplified Spectroscopic Survey
Fontana, Adriano; Pentericci, Laura; Schmidt, Kasper B. +12 more
Detections and non-detections of Lyman alpha (Lyα) emission from z > 6 galaxies (<1 Gyr after the big bang) can be used to measure the timeline of cosmic reionization. Of key interest to measuring reionization's mid-stages, but also increasing observational challenge, are observations at z > 7, where Lyα redshifts to near infra-red wavele…
Age determination for 269 Gaia DR2 open clusters
Jordi, C.; Casamiquela, L.; Cantat-Gaudin, T. +9 more
Context. The Gaia Second Data Release provides precise astrometry and photometry for more than 1.3 billion sources. This catalog opens a new era concerning the characterization of open clusters and test stellar models, paving the way for better understanding of the disk properties.
Aims: The aim of the paper is to improve the knowledge of clu…
Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus
Read, A. M.; Knigge, C.; Heywood, I. +11 more
In the past two decades, high-amplitude electromagnetic outbursts have been detected from dormant galaxies and often attributed to the tidal disruption of a star by the central black hole1,2. X-ray emission from the Seyfert 2 galaxy GSN 069 (2MASX J01190869-3411305) at a redshift of z = 0.018 was first detected in July 2010 and implies …
Mass and shape of the Milky Way's dark matter halo with globular clusters from Gaia and Hubble
Helmi, Amina; Posti, Lorenzo
Aims: We estimate the mass of the inner (< 20 kpc) Milky Way and the axis ratio of its inner dark matter halo using globular clusters as tracers. At the same time, we constrain the distribution in phase-space of the globular cluster system around the Galaxy.
Methods: We use the Gaia Data Release 2 catalogue of 75 globular clusters' pr…
Multiple retrograde substructures in the Galactic halo: A shattered view of Galactic history
Price-Whelan, Adrian M.; Helmi, Amina; Koppelman, Helmer H. +2 more
Aims: Several kinematic and chemical substructures have been recently found amongst Milky Way halo stars with retrograde motions. It is currently unclear how these various structures are related to each other. This Letter aims to shed light on this issue.
Methods: We explore the retrograde halo with an augmented version of the Gaia DR2 R…
Confirmation of the Gaia DR2 Parallax Zero-point Offset Using Asteroseismology and Spectroscopy in the Kepler Field
Huber, Daniel; Stello, Dennis; Pinsonneault, Marc H. +1 more
We present an independent confirmation of the zero-point offset of Gaia Data Release 2 parallaxes using asteroseismic data of evolved stars in the Kepler field. Using well-characterized red giant branch stars from the APOKASC-2 catalog, we identify a Gaia astrometric pseudocolor ({ν }eff})- and Gaia G-band magnitude-dependent zero-point…
Water vapour in the atmosphere of the habitable-zone eight-Earth-mass planet K2-18 b
Tsiaras, Angelos; Tinetti, Giovanna; Yurchenko, Sergey N. +2 more
In the past decade, observations from space and the ground have found water to be the most abundant molecular species, after hydrogen, in the atmospheres of hot, gaseous extrasolar planets1-5. Being the main molecular carrier of oxygen, water is a tracer of the origin and the evolution mechanisms of planets. For temperate, terrestrial p…
A dominant population of optically invisible massive galaxies in the early Universe
Elbaz, D.; Franco, M.; Shu, X. +9 more
Our current knowledge of cosmic star-formation history during the first two billion years (corresponding to redshift z > 3) is mainly based on galaxies identified in rest-frame ultraviolet light1. However, this population of galaxies is known to under-represent the most massive galaxies, which have rich dust content and/or old stella…
Massive runaway and walkaway stars. A study of the kinematical imprints of the physical processes governing the evolution and explosion of their binary progenitors
Renzo, M.; Zapartas, E.; de Mink, S. E. +6 more
We perform an extensive numerical study of the evolution of massive binary systems to predict the peculiar velocities that stars obtain when their companion collapses and disrupts the system. Our aim is to (i) identify which predictions are robust against model uncertainties and assess their implications, (ii) investigate which physical processes …