Search Publications
Reverse engineering the Milky Way
Forbes, Duncan A.
The ages, metallicities, alpha-elements, and integrals of motion of globular clusters (GCs) accreted by the Milky Way from disrupted satellites remain largely unchanged over time. Here we have used these conserved properties in combination to assign 76 GCs to five progenitor satellite galaxies - one of which we dub the Koala dwarf galaxy. We fit a…
When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147
Torres, Guillermo; Vanderburg, Andrew; Latham, David W. +17 more
Recent measurements of rotation periods ( ${P}_{\mathrm{rot}}$ ) in the benchmark open clusters Praesepe (670 Myr), NGC 6811 (1 Gyr), and NGC 752 (1.4 Gyr) demonstrate that, after converging onto a tight sequence of slowly rotating stars in mass-period space, stars temporarily stop spinning down. These data also show that the duration of this epoc…
The Destruction and Recreation of the X-Ray Corona in a Changing-look Active Galactic Nucleus
Altamirano, D.; Fabian, A. C.; Gandhi, P. +16 more
We present the drastic transformation of the X-ray properties of the active galactic nucleus (AGN) 1ES 1927+654, following a changing-look event. After the optical/ultraviolet outburst the power-law component, produced in the X-ray corona, disappeared, and the spectrum of 1ES 1927+65 instead became dominated by a blackbody component (kT ∼ 80-120 e…
A Galactic-scale gas wave in the solar neighbourhood
Meingast, Stefan; Alves, João; Speagle, Joshua S. +6 more
For the past 150 years, the prevailing view of the local interstellar medium has been based on a peculiarity known as the Gould Belt1-4, an expanding ring of young stars, gas and dust, tilted about 20 degrees to the Galactic plane. However, the physical relationship between local gas clouds has remained unknown because the accuracy in d…
An excess of small-scale gravitational lenses observed in galaxy clusters
Grillo, Claudio; Rosati, Piero; Meneghetti, Massimo +11 more
Cold dark matter (CDM) constitutes most of the matter in the Universe. The interplay between dark and luminous matter in dense cosmic environments, such as galaxy clusters, is studied theoretically using cosmological simulations. Observations of gravitational lensing are used to characterize the properties of substructures—the small-scale distribu…
Constraining the thermally pulsing asymptotic giant branch phase with resolved stellar populations in the Large Magellanic Cloud
Boyer, Martha L.; Girardi, Léo; de Grijs, Richard +18 more
Reliable models of the thermally pulsing asymptotic giant branch (TP-AGB) phase are of critical importance across astrophysics, including our interpretation of the spectral energy distribution of galaxies, cosmic dust production, and enrichment of the interstellar medium. With the aim of improving sets of stellar isochrones that include a detailed…
The Sixth Data Release of the Radial Velocity Experiment (RAVE). I. Survey Description, Spectra, and Radial Velocities
Grebel, Eva K.; Chaplin, William J.; Steinmetz, Matthias +60 more
The Radial Velocity Experiment (RAVE) is a magnitude-limited (9 < I < 12) spectroscopic survey of Galactic stars randomly selected in Earth's southern hemisphere. The RAVE medium-resolution spectra (R ∼ 7500) cover the Ca-triplet region (8410-8795 Å). The sixth and final data release (DR6) is based on 518,387 observations of 451,783 unique s…
ALMA uncovers the [C II] emission and warm dust continuum in a z = 8.31 Lyman break galaxy
Shibuya, Takatoshi; Inoue, Akio K.; Hashimoto, Takuya +15 more
We report on the detection of the [C II] 157.7 µm emission from the Lyman break galaxy (LBG) MACS0416_Y1 at z = 8.3113, by using the Atacama Large Millimeter/submillimeter Array (ALMA). The luminosity ratio of [O III] 88 µm (from previous campaigns) to [C II] is 9.3 ± 2.6, indicative of hard interstellar radiation fields and/or a low c…
Texas Spectroscopic Search for Lyα Emission at the End of Reionization. III. The Lyα Equivalent-width Distribution and Ionized Structures at z > 7
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +11 more
Lyα emission from galaxies can be utilized to characterize the ionization state in the intergalactic medium (IGM). We report our search for Lyα emission at z > 7 using a comprehensive Keck/MOSFIRE near-infrared spectroscopic data set, as part of the Texas Spectroscopic Search for Lyα Emission at the End of Reionization Survey. We analyze data f…
Resolving nearby dust clouds
Enßlin, T. A.; Leike, R. H.; Glatzle, M.
Aims: Mapping the interstellar medium in 3D provides a wealth of insights into its inner working. The Milky Way is the only galaxy for which detailed 3D mapping can be achieved in principle. In this paper, we reconstruct the dust density in and around the local super-bubble.
Methods: The combined data from surveys such as Gaia, 2MASS, PA…