Search Publications
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…
SILVERRUSH. VIII. Spectroscopic Identifications of Early Large-scale Structures with Protoclusters over 200 Mpc at z ∼ 6-7: Strong Associations of Dusty Star-forming Galaxies
Ono, Yoshiaki; Ouchi, Masami; Goto, Tomotsugu +32 more
We have obtained three-dimensional maps of the universe in ∼200 × 200 × 80 comoving Mpc3 (cMpc3) volumes each at z = 5.7 and 6.6 based on a spectroscopic sample of 179 galaxies that achieves ≳80% completeness down to the Lyα luminosity of {log}({L}Lyα }/[{erg} {{{s}}}-1])=43.0, based on our Keck and Gemi…
Resolved Young Binary Systems and Their Disks
Jensen, Eric L. N.; Carpenter, John; Ricci, Luca +4 more
We have conducted a survey of young single and multiple systems in the Taurus-Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separ…
A New Class of Changing-look LINERs
Cenko, S. Bradley; Duev, Dmitry A.; Rusholme, Ben +28 more
We report the discovery of six active galactic nuclei (AGNs) caught “turning on” during the first nine months of the Zwicky Transient Facility (ZTF) survey. The host galaxies were classified as low-ionization nuclear emission-line region galaxies (LINERs) by weak narrow forbidden line emission in their archival SDSS spectra, and detected by ZTF as…