Search Publications
The CO Luminosity Density at High-z (COLDz) Survey: A Sensitive, Large-area Blind Search for Low-J CO Emission from Cold Gas in the Early Universe with the Karl G. Jansky Very Large Array
Dickinson, Mark; Smail, Ian; Daddi, Emanuele +16 more
We describe the CO Luminosity Density at High-z (COLDz) survey, the first spectral line deep field targeting CO(1-0) emission from galaxies at z = 1.95-2.85 and CO(2-1) at z = 4.91-6.70. The main goal of COLDz is to constrain the cosmic density of molecular gas at the peak epoch of cosmic star formation. By targeting both a wide (∼51 arcmin2<…
Hitomi (ASTRO-H) X-ray Astronomy Satellite
Done, Chris; Safi-Harb, Samar; Hamaguchi, Kenji +267 more
The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decade…
The 1.5 Ms observing campaign on IRAS 13224-3809 - I. X-ray spectral analysis
Harrison, F. A.; Fabian, A. C.; Miller, J. M. +16 more
We present a detailed spectral analysis of the recent 1.5 Ms XMM-Newton observing campaign on the narrow-line Seyfert 1 galaxy IRAS 13224-3809, taken simultaneously with 500 ks of NuSTAR data. The X-ray light curve shows three flux peaks, registering at about 100 times the minimum flux seen during the campaign, and rapid variability with a time-sc…
Production of Cool Gas in Thermally Driven Outflows
Robertson, Brant E.; Thompson, Todd A.; Schneider, Evan E.
Galactic outflows commonly contain multiphase gas, and its physical origin requires explanation. Using the Cholla Galactic OutfLow Simulations suite of high-resolution isolated galaxy models, we demonstrate the viability of rapid radiative cooling as a source of fast-moving (v ∼ 1000 km s-1), cool (104 K) gas observed in abso…
Hubble Space Telescope Observations of Extended [O III]λ 5007 Emission in Nearby QSO2s: New Constraints on AGN Host Galaxy Interaction
Turner, T. J.; Kraemer, S. B.; Crenshaw, D. M. +15 more
We present a Hubble Space Telescope survey of extended [O III] λ5007 emission for a sample of 12 nearby (z < 0.12), luminous Type 2 quasars (QSO2s), which we use to measure the extent and kinematics of their AGN-ionized gas. We find that the size of the observed [O III] regions scale with luminosity in comparison to nearby, less luminous Seyfer…
Successive X-class Flares and Coronal Mass Ejections Driven by Shearing Motion and Sunspot Rotation in Active Region NOAA 12673
Feng, X. S.; Yan, X. L.; Xue, Z. K. +5 more
We present a clear case study on the occurrence of two successive X-class flares, including a decade-class flare (X9.3) and two coronal mass ejections (CMEs) triggered by shearing motion and sunspot rotation in active region NOAA 12673 on 2017 September 6. A shearing motion between the main sunspots with opposite polarities began on September 5 an…
High-precision stellar abundances of the elements: methods and applications
Nissen, Poul Erik; Gustafsson, Bengt
Efficient spectrographs at large telescopes have made it possible to obtain high-resolution spectra of stars with high signal-to-noise ratio and advances in model atmosphere analyses have enabled estimates of high-precision differential abundances of the elements from these spectra, i.e. with errors in the range 0.01-0.03 dex for F, G, and K stars…
The Disk Substructures at High Angular Resolution Project (DSHARP). X. Multiple Rings, a Misaligned Inner Disk, and a Bright Arc in the Disk around the T Tauri star HD 143006
Wilner, David J.; Andrews, Sean M.; Guzmán, Viviana V. +14 more
We present a detailed analysis of new Atacama Large Millimeter/submillimeter Array (ALMA) observations of the disk around the T-Tauri star HD 143006, which at 46 mas (7.6 au) resolution reveals new substructures in the 1.25 mm continuum emission. The disk resolves into a series of concentric rings and gaps, together with a bright arc exterior to t…
Measuring the Recoverability of Close Binaries in Gaia DR2 with the Robo-AO Kepler Survey
Baranec, Christoph; Law, Nicholas M.; Riddle, Reed +6 more
We use the Robo-AO survey of Kepler planetary candidate host stars, the largest adaptive optics survey yet performed, to measure the recovery rate of close stellar binaries in Gaia DR2. We find that Gaia recovers binaries down to 1″ at magnitude contrasts as large as six; closer systems are not resolved, regardless of secondary brightness. Gaia DR…
Distances and Kinematics of Gould Belt Star-forming Regions with Gaia DR2 Results
Rodríguez, Luis F.; Loinard, Laurent; Ortiz-León, Gisela N. +2 more
We present an analysis of the astrometric results from the Gaia second data release (DR2) for young stellar objects (YSOs) in star-forming regions related to the Gould Belt (GB). These regions are Barnard 59, Lupus 1 to 4, Chamaeleon I and II, ɛ Chamaeleontis, the Cepheus flare, IC 5146, and Corona Australis. The mean distance to the YSOs in each …