Search Publications
Full-data Results of Hubble Frontier Fields: UV Luminosity Functions at z ∼ 6-10 and a Consistent Picture of Cosmic Reionization
Ono, Yoshiaki; Ouchi, Masami; Shimasaku, Kazuhiro +3 more
We present UV luminosity functions of dropout galaxies at z∼ 6{--}10 with the complete Hubble Frontier Fields data. We obtain a catalog of ∼450 dropout-galaxy candidates (350, 66, and 40 at z∼ 6{--}7, 8, and 9, respectively), with UV absolute magnitudes that reach ∼ -14 mag, ∼2 mag deeper than the Hubble Ultra Deep Field detection limits. We caref…
Revised Radii of Kepler Stars and Planets Using Gaia Data Release 2
van Saders, Jennifer L.; Huber, Daniel; Berger, Travis A. +1 more
One bottleneck for the exploitation of data from the Kepler mission for stellar astrophysics and exoplanet research has been the lack of precise radii and evolutionary states for most of the observed stars. We report revised radii of 177,911 Kepler stars derived by combining parallaxes from the Gaia Data Release 2 with the DR25 Kepler Stellar Prop…
Evidence for a Systematic Offset of -80 µas in the Gaia DR2 Parallaxes
Torres, Guillermo; Stassun, Keivan G.
We reprise the analysis of Stassun & Torres, comparing the parallaxes of the eclipsing binaries reported in that paper to the parallaxes newly reported in the Gaia second data release (DR2). We find evidence for a systematic offset of -82 ± 33 µas, in the sense of the Gaia parallaxes being too small, for brightnesses (G ≲ 12) and for dis…
Kinematic Evidence for an Embedded Protoplanet in a Circumstellar Disk
Pinte, C.; Ménard, F.; Duchêne, G. +6 more
Disks of gas and dust surrounding young stars are the birthplace of planets. However, the direct detection of protoplanets forming within disks has proved elusive to date. We present the detection of a large, localized deviation from Keplerian velocity in the protoplanetary disk surrounding the young star HD 163296. The observed velocity pattern i…
A Kinematical Detection of Two Embedded Jupiter-mass Planets in HD 163296
Foreman-Mackey, Daniel; Bae, Jaehan; Bergin, Edwin A. +2 more
We present the first kinematical detection of embedded protoplanets within a protoplanetary disk. Using archival Atacama Large Millimetre Array (ALMA) observations of HD 163296, we demonstrate a new technique to measure the rotation curves of CO isotopologue emission to sub-percent precision relative to the Keplerian rotation. These rotation curve…
Elucidating ΛCDM: Impact of Baryon Acoustic Oscillation Measurements on the Hubble Constant Discrepancy
Halpern, M.; Weiland, J. L.; Hinshaw, G. +3 more
We examine the impact of baryon acoustic oscillation (BAO) scale measurements on the discrepancy between the value of the Hubble constant (H 0) inferred from the local distance ladder and that from Planck cosmic microwave background (CMB) data. While the BAO data alone cannot constrain H 0, we show that combining the latest B…
H- Opacity and Water Dissociation in the Dayside Atmosphere of the Very Hot Gas Giant WASP-18b
Fortney, Jonathan J.; Stevenson, Kevin B.; Désert, Jean-Michel +7 more
We present one of the most precise emission spectra of an exoplanet observed so far. We combine five secondary eclipses of the hot Jupiter WASP-18b (T day ∼ 2900 K) that we secured between 1.1 and 1.7 µm with the Wide Field Camera 3 instrument on board the Hubble Space Telescope. Our extracted spectrum (S/N = 50, R ∼ 40) does not …
Type Ia Supernova Distances at Redshift >1.5 from the Hubble Space Telescope Multi-cycle Treasury Programs: The Early Expansion Rate
Dickinson, Mark; Ferguson, Henry C.; Grogin, Norman A. +31 more
We present an analysis of 15 Type Ia supernovae (SNe Ia) at redshift z> 1 (9 at 1.5< z< 2.3) recently discovered in the CANDELS and CLASH Multi-Cycle Treasury programs using WFC3 on the Hubble Space Telescope. We combine these SNe Ia with a new compilation of ∼1050 SNe Ia, jointly calibrated and corrected for simulated survey biases to pr…
Extremely Irradiated Hot Jupiters: Non-oxide Inversions, H- Opacity, and Thermal Dissociation of Molecules
Lothringer, Joshua D.; Barman, Travis; Koskinen, Tommi
Extremely irradiated hot Jupiters, exoplanets reaching dayside temperatures >2000 K, stretch our understanding of planetary atmospheres and the models we use to interpret observations. While these objects are planets in every other sense, their atmospheres reach temperatures at low pressures comparable only to stellar atmospheres. In order to u…
The ATLAS All-Sky Stellar Reference Catalog
Wolf, C.; Smartt, S. J.; Stalder, B. +6 more
The Asteroid Terrestrial-impact Last Alert System (ATLAS) observes most of the sky every night in search of dangerous asteroids. Its data are also used to search for photometric variability, where sensitivity to variability is limited by photometric accuracy. Since each exposure spans 7.°6 corner to corner, variations in atmospheric transparency i…