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The Kepler Follow-up Observation Program. I. A Catalog of Companions to Kepler Stars from High-Resolution Imaging
DOI: 10.3847/1538-3881/153/2/71 Bibcode: 2017AJ....153...71F

Teske, J. K.; Barrado, D.; Ciardi, D. R. +16 more

We present results from high-resolution, optical to near-IR imaging of host stars of Kepler Objects of Interest (KOIs), identified in the original Kepler field. Part of the data were obtained under the Kepler imaging follow-up observation program over six years (2009-2015). Almost 90% of stars that are hosts to planet candidates or confirmed plane…

2017 The Astronomical Journal
eHST 201
Spitzer Phase Curve Constraints for WASP-43b at 3.6 and 4.5 µm
DOI: 10.3847/1538-3881/153/2/68 Bibcode: 2017AJ....153...68S

Fortney, Jonathan J.; Stevenson, Kevin B.; Kataria, Tiffany +6 more

Previous measurements of heat redistribution efficiency (the ability to transport energy from a planet’s highly irradiated dayside to its eternally dark nightside) show considerable variation between exoplanets. Theoretical models predict a positive correlation between heat redistribution efficiency and temperature for tidally locked planets; howe…

2017 The Astronomical Journal
eHST 151
Trends in Atmospheric Properties of Neptune-size Exoplanets
DOI: 10.3847/1538-3881/aa9279 Bibcode: 2017AJ....154..261C

Crossfield, Ian J. M.; Kreidberg, Laura

Precise atmospheric observations have been made for a growing sample of warm Neptunes. Here, we investigate the correlations between these observations and a large number of system parameters to show that, at 95% confidence, the amplitude of a warm Neptune's spectral features in transmission correlates with either its equilibrium temperature (T

2017 The Astronomical Journal
eHST 141
A New Stellar Atmosphere Grid and Comparisons with HST/STIS CALSPEC Flux Distributions
DOI: 10.3847/1538-3881/aa6ba9 Bibcode: 2017AJ....153..234B

Koekemoer, Anton M.; Gordon, Karl D.; Bohlin, Ralph C. +3 more

The Space Telescope Imaging Spectrograph has measured the spectral energy distributions for several stars of types O, B, A, F, and G. These absolute fluxes from the CALSPEC database are fit with a new spectral grid computed from the ATLAS-APOGEE ATLAS9 model atmosphere database using a chi-square minimization technique in four parameters. The qual…

2017 The Astronomical Journal
eHST 135
Forward and Inverse Modeling of the Emission and Transmission Spectrum of GJ 436b: Investigating Metal Enrichment, Tidal Heating, and Clouds
DOI: 10.3847/1538-3881/153/2/86 Bibcode: 2017AJ....153...86M

Knutson, Heather; Fortney, Jonathan J.; Marley, Mark S. +5 more

The Neptune-mass GJ 436b is one of the most studied transiting exoplanets with repeated measurements of its thermal emission and transmission spectra. We build on previous studies to answer outstanding questions about this planet, including its potentially high metallicity and tidal heating of its interior. We present new observations of GJ 436b’s…

2017 The Astronomical Journal
eHST 112
Accurate Distances to Important Spiral Galaxies: M63, M74, NGC 1291, NGC 4559, NGC 4625, and NGC 5398
DOI: 10.3847/1538-3881/aa7aad Bibcode: 2017AJ....154...51M

Dolphin, Andrew E.; Skillman, Evan D.; Berg, Danielle +2 more

Accurate distances are fundamental for interpreting various measured properties of galaxies. Surprisingly, many of the best-studied spiral galaxies in the Local Volume have distance uncertainties that are much larger than can be achieved with modern observation techniques. Using Hubble Space Telescopeoptical imaging, we use the tip of the red gian…

2017 The Astronomical Journal
eHST 89
Temporal Evolution of the High-energy Irradiation and Water Content of TRAPPIST-1 Exoplanets
DOI: 10.3847/1538-3881/aa859c Bibcode: 2017AJ....154..121B

Delrez, L.; Demory, B. -O.; Ehrenreich, D. +13 more

The ultracool dwarf star TRAPPIST-1 hosts seven Earth-size transiting planets, some of which could harbor liquid water on their surfaces. Ultraviolet observations are essential to measuring their high-energy irradiation and searching for photodissociated water escaping from their putative atmospheres. Our new observations of the TRAPPIST-1 Lyα lin…

2017 The Astronomical Journal
eHST 83
A Physical Model-based Correction for Charge Traps in the Hubble Space Telescope’s Wide Field Camera 3 Near-IR Detector and Its Applications to Transiting Exoplanets and Brown Dwarfs
DOI: 10.3847/1538-3881/aa6481 Bibcode: 2017AJ....153..243Z

Schneider, Glenn; Apai, Dániel; Zhou, Yifan +1 more

The Hubble Space Telescope Wide Field Camera 3 (WFC3) near-IR channel is extensively used in time-resolved observations, especially for transiting exoplanet spectroscopy as well as brown dwarf and directly imaged exoplanet rotational phase mapping. The ramp effect is the dominant source of systematics in the WFC3 for time-resolved observations, wh…

2017 The Astronomical Journal
eHST 79
Evidence for Atmospheric Cold-trap Processes in the Noninverted Emission Spectrum of Kepler-13Ab Using HST/WFC3
DOI: 10.3847/1538-3881/aa899b Bibcode: 2017AJ....154..158B

Madhusudhan, Nikku; Knutson, Heather A.; Wright, Jason T. +5 more

We observed two eclipses of the Kepler-13A planetary system, on UT 2014 April 28 and UT 2014 October 13, in the near-infrared using Wide Field Camera 3 on the Hubble Space Telescope. By using the nearby binary stars Kepler-13BC as a reference, we were able to create a differential light curve for Kepler-13A that had little of the systematics typic…

2017 The Astronomical Journal
eHST 57
The SEEDS High-Contrast Imaging Survey of Exoplanets Around Young Stellar Objects
DOI: 10.3847/1538-3881/153/3/106 Bibcode: 2017AJ....153..106U

Henning, Thomas; Terada, Hiroshi; Usuda, Tomonori +49 more

We present high-contrast observations of 68 young stellar objects (YSOs) that have been explored as part of the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) survey on the Subaru telescope. Our targets are very young (<10 Myr) stars, which often harbor protoplanetary disks where planets may be forming. We achieve a typical c…

2017 The Astronomical Journal
eHST 55