Search Publications
On the dust temperatures of high-redshift galaxies
Faucher-Giguère, Claude-André; Hayward, Christopher C.; Hopkins, Philip F. +7 more
Dust temperature is an important property of the interstellar medium (ISM) of galaxies. It is required when converting (sub)millimetre broad-band flux to total infrared luminosity (LIR), and hence star formation rate, in high-redshift galaxies. However, different definitions of dust temperatures have been used in the literature, leading…
Is the dark-matter halo spin a predictor of galaxy spin and size?
Somerville, Rachel S.; Genel, Shy; Dekel, Avishai +8 more
The similarity between the distributions of spins for galaxies (λgal) and for dark-matter haloes (λhalo), indicated both by simulations and observations, is naively interpreted as a one-to-one correlation between the spins of a galaxy and its host halo. This is used to predict galaxy sizes in semi-analytic models via Re<…
A radio ridge connecting two galaxy clusters in a filament of the cosmic web
Brunetti, G.; Enßlin, T. A.; Shimwell, T. W. +26 more
Galaxy clusters are the most massive gravitationally bound structures in the Universe. They grow by accreting smaller structures in a merging process that produces shocks and turbulence in the intracluster gas. We observed a ridge of radio emission connecting the merging galaxy clusters Abell 0399 and Abell 0401 with the Low-Frequency Array (LOFAR…
The Chemical Evolution of Carbon, Nitrogen, and Oxygen in Metal-poor Dwarf Galaxies
McQuinn, Kristen B. W.; Skillman, Evan D.; Erb, Dawn K. +2 more
Ultraviolet nebular emission lines are important for understanding the time evolution and nucleosynthetic origins of their associated elements, but the underlying trends of their relative abundances are unclear. We present UV spectroscopy of 20 nearby low-metallicity, high-ionization dwarf galaxies obtained using the Hubble Space Telescope. Buildi…
Gravitational lensing reveals ionizing ultraviolet photons escaping from a distant galaxy
Mahler, Guillaume; Chisholm, John; Rigby, Jane R. +7 more
During the epoch of reionization, neutral gas in the early Universe was ionized by hard ultraviolet radiation emitted by young stars in the first galaxies. To do so, ionizing ultraviolet photons must escape from the host galaxy. We present Hubble Space Telescope observations of the gravitationally lensed post-reionization galaxy PSZ1-ARC G311.6602…
Models and Simulations for the Photometric LSST Astronomical Time Series Classification Challenge (PLAsTiCC)
Galbany, L.; Brown, P. J.; González-Gaitán, S. +28 more
We describe the simulated data sample for the Photometric Large Synoptic Survey Telescope (LSST) Astronomical Time Series Classification Challenge (PLAsTiCC), a publicly available challenge to classify transient and variable events that will be observed by the LSST, a new facility expected to start in the early 2020s. The challenge was hosted by K…
First Identification of 10 kpc [C II] 158 µm Halos around Star-forming Galaxies at z = 5-7
Ouchi, Masami; Ivison, R. J.; Fujimoto, Seiji +7 more
We report the discovery of 10 kpc [C II] 158 µm halos surrounding star-forming galaxies in the early universe. We choose deep Atacama Large Millimeter/submillimeter Array data for 18 galaxies, each with a star formation rate of ≃10-70 M ⊙ with no signature of an active galactic nucleus whose [C II] lines are individually detected …
Precise Dynamical Masses of Directly Imaged Companions from Relative Astrometry, Radial Velocities, and Hipparcos-Gaia DR2 Accelerations
Dupuy, Trent J.; Bowler, Brendan P.; Brandt, Timothy D.
We measure dynamical masses for five objects—three ultracool dwarfs, one low-mass star, and one white dwarf—by fitting orbits to a combination of the Hipparcos-Gaia Catalog of Accelerations, literature radial velocities, and relative astrometry. Our approach provides precise masses without any assumptions about the primary star, even though the ob…
STiC: A multiatom non-LTE PRD inversion code for full-Stokes solar observations
Leenaarts, J.; Danilovic, S.; de la Cruz Rodríguez, J. +1 more
The inference of the underlying state of the plasma in the solar chromosphere remains extremely challenging because of the nonlocal character of the observed radiation and plasma conditions in this layer. Inversion methods allow us to derive a model atmosphere that can reproduce the observed spectra by undertaking several physical assumptions. The…
Tension with the flat ΛCDM model from a high-redshift Hubble diagram of supernovae, quasars, and gamma-ray bursts
Paolillo, M.; Nardini, E.; Amati, L. +4 more
In the current framework, the standard parametrization of our Universe is the so-called Lambda cold dark matter (ΛCDM) model. Recently, a ∼4σ tension with the ΛCDM model was shown to exist via a model-independent parametrization of a Hubble diagram of type Ia supernovae (SNe Ia) from the JLA survey and quasars. Model-independent approaches and ind…