Search Publications
X-Ray Properties of SPT-selected Galaxy Clusters at 0.2 < z < 1.5 Observed with XMM-Newton
Miller, Eric D.; Schrabback, Tim; Holzapfel, W. L. +22 more
We present measurements of the X-ray observables of the intracluster medium (ICM), including luminosity L X , ICM mass M ICM, emission-weighted mean temperature T X , and integrated pressure Y X , that are derived from XMM-Newton X-ray observations of a Sunyaev-Zel’dovich effect (SZE) selected sample …
The Analogous Structure of Accretion Flows in Supermassive and Stellar Mass Black Holes: New Insights from Faded Changing-look Quasars
Green, Paul J.; Anderson, Scott F.; Eracleous, Michael +5 more
Despite their factor of ∼108 difference in black hole mass, several lines of evidence suggest possible similarities between black hole accretion flows in active galactic nuclei (AGN) and Galactic X-ray binaries. However, it is still unclear whether the geometry of the disk-corona system in X-ray binaries directly scales up to AGN and wh…
Resolving the Metallicity Distribution of the Stellar Halo with the H3 Survey
Conroy, Charlie; Johnson, Benjamin D.; Caldwell, Nelson +4 more
The Galactic stellar halo is predicted to have formed at least partially from the tidal disruption of accreted dwarf galaxies. This assembly history should be detectable in the orbital and chemical properties of stars. The H3 Survey is obtaining spectra for 200,000 stars and, when combined with Gaia data, is providing detailed orbital and chemical…
The Brightest z ≳ 8 Galaxies over the COSMOS UltraVISTA Field
Franx, Marijn; Illingworth, Garth D.; Muzzin, Adam +12 more
We present 16 new ultrabright H AB ≲ 25 galaxy candidates at z ∼ 8 identified over the COSMOS/UltraVISTA field. The new search takes advantage of the deepest-available ground-based optical and near-infrared observations, including the DR3 release of UltraVISTA and full-depth Spitzer/IRAC observations from the SMUVS and SPLASH programs…
Spatially Resolved Stellar Kinematics of the Ultra-diffuse Galaxy Dragonfly 44. I. Observations, Kinematics, and Cold Dark Matter Halo Fits
van Dokkum, Pieter; Forbes, Duncan A.; Romanowsky, Aaron J. +8 more
We present spatially resolved stellar kinematics of the well-studied ultra-diffuse galaxy (UDG) Dragonfly 44, as determined from 25.3 hr of observations with the Keck Cosmic Web Imager. The luminosity-weighted dispersion within the half-light radius is {σ }1/2={33}-3+3 km s-1, lower than what we had infe…
Super-efficient Electron Acceleration by an Isolated Magnetic Reconnection
Vaivads, A.; Xu, Y.; Fu, H. S. +1 more
Magnetic reconnection—the process typically lasting for a few seconds in space—is able to accelerate electrons. However, the efficiency of the acceleration during such a short period is still a puzzle. Previous analyses, based on spacecraft measurements in the Earth’s magnetotail, indicate that magnetic reconnection can enhance electron fluxes up …
The Faint End of the Centaurus A Satellite Luminosity Function
Crnojević, D.; Sand, D. J.; Simon, J. D. +9 more
The Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) is constructing a wide-field map of the resolved stellar populations in the extended halos of these two nearby, prominent galaxies. We present new Magellan/Megacam imaging of a ∼3 deg2 area around Centaurus A (Cen A), which filled in much of our coverage to its south, leavi…
New Insights on Lyα and Lyman Continuum Radiative Transfer in the Greenest Peas
Scarlata, Claudia; Jaskot, Anne E.; Dowd, Tara +2 more
As some of the only Lyman continuum (LyC) emitters at z ∼ 0, Green Pea (GP) galaxies are possible analogs of the sources that reionized the universe. We present HST COS spectra of 13 of the most highly ionized GPs, with [O III]/[O II] = 6-35, and investigate correlations between Lyα, galaxy properties, and low-ionization UV lines. Galaxies with hi…
First Gaia Dynamics of the Andromeda System: DR2 Proper Motions, Orbits, and Rotation of M31 and M33
van der Marel, Roeland P.; Watkins, Laura L.; Fardal, Mark A. +5 more
The 3D velocities of M31 and M33 are important for understanding the evolution and cosmological context of the Local Group. Their most massive stars are detected by Gaia, and we use Data Release 2 (DR2) to determine the galaxy proper motions (PMs). We select galaxy members based on, e.g., parallax, PM, color-magnitude diagram location, and local s…
SDSS-IV MaStar: A Large and Comprehensive Empirical Stellar Spectral Library—First Release
Zhao, Gang; Bizyaev, Dmitry; Kinemuchi, Karen +45 more
We present the first release of the MaNGA Stellar Library (MaStar), which is a large, well-calibrated, high-quality empirical library covering the wavelength range 3622-10354 Å at a resolving power of R ∼ 1800. The spectra were obtained using the same instrument as used by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, by…