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The mass of the neutron star in Vela X-1 and tidally induced non-radial oscillations in GP Vel
We report new radial velocity observations of GP Vel / HD 77581, the optical companion to the eclipsing X-ray pulsar Vela X-1. Using data spanning more than two complete orbits of the system, we
Revised Stellar Properties of Kepler Targets for the Quarter 1-16 Transit Detection Run
We present revised properties for 196,468 stars observed by the NASA Kepler mission and used in the analysis of Quarter 1-16 (Q1-Q16) data to detect and characterize transiting planets. The catalog
Correcting Stellar Oscillation Frequencies for Near-Surface Effects
In helioseismology, there is a well-known offset between observed and computed oscillation frequencies. This offset is known to arise from improper modeling of the near-surface layers of the Sun, and
Accurate fundamental parameters for 23 bright solar-type stars
We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, from spectral type F5 to K2 and luminosity
Masses, Radii, and Orbits of Small Kepler Planets: The Transition From Gaseous to Rocky Planets
We report on the masses, sizes, and orbits of the planets orbiting 22 Kepler stars. There are 49 planet candidates around these stars, including 42 detected through transits and 7 revealed by precise
A close halo of large transparent grains around extreme red giant stars
Spatially resolved, multiwavelength observations of circumstellar dust shells of three stars on the asymptotic giant branch of the Hertzsprung–Russell diagram show that transparency usually implies insufficient radiative pressure to drive a wind, the radiation field can accelerate these large grains through photon scattering rather than absorption—a plausible mass loss mechanism for lower-amplitude pulsating stars.
Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities
Another violation of the orbit-composition pattern is reported: two planets orbiting the same star with orbital distances differing by only 10% and densities differing by a factor of 8, likely a rocky “super-Earth,” whereas the other is more akin to Neptune.
Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology
We present a study of 33 {\it Kepler} planet-candidate host stars for which asteroseismic observations have sufficiently high signal-to-noise ratio to allow extraction of individual pulsation
We have used asteroseismology to determine fundamental properties for 66 Kepler planet-candidate host stars, with typical uncertainties of 3% and 7% in radius and mass, respectively. The results
Accurate fundamental parameters and detailed abundance patterns from spectroscopy of 93 solar-type Kepler targets
We present a detailed spectroscopic study of 93 solar-type stars that are targets of the NASA/Kepler mission and provide detailed chemical composition of each target. We find that the overall