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KELT-19Ab: A P ∼ 4.6-day Hot Jupiter Transiting a Likely Am Star with a Distant Stellar Companion
Bieryla, Allyson; Latham, David W.; Quinn, Samuel N. +51 more
We present the discovery of the giant planet KELT-19Ab, which transits the moderately bright (V∼ 9.9) A8V star TYC 764-1494-1 with an orbital period of 4.61 days. We confirm the planetary nature of the companion via a combination of radial velocities, which limit the mass to ≲ 4.1 {M}{{J}} (3σ ), and a clear Doppler tomography signal, w…
The Radial Velocity Variability of the K-giant γ Draconis: Stellar Variability Masquerading as a Planet
Dreizler, S.; Hatzes, A. P.; Cochran, W. D. +9 more
We present precise stellar radial velocity (RV) measurements of γ Dra taken from 2003 to 2017. The data from 2003 to 2011 show coherent, long-lived variations with a period of 702 days. These variations are consistent with the presence of a planetary companion having m sin i = 10.7 M Jup whose orbital properties are typical for giant pl…
Speckle Interferometry at SOAR in 2016 and 2017
Tokovinin, Andrei; Horch, Elliott P.; Mason, Brian D. +2 more
The results of speckle interferometric observations at the 4.1 m Southern Astrophysical Research Telescope in 2016 and 2017 are given, totaling 2483 measurements of 1570 resolved pairs and 609 non-resolutions. We describe briefly recent changes in the instrument and observing method and quantify the accuracy of the pixel scale and position angle c…
Spectroscopic Orbits of Subsystems in Multiple Stars. III.
Tokovinin, Andrei
Spectroscopic orbits are computed for inner pairs in six nearby hierarchical multiple systems (HIP 35733, 95106/95110, 105441, 105585/105569, 105947, and 109951). Radial velocities and resolved measurements, when available, are used to derive combined sets of outer orbital elements for three systems. Each multiple system is discussed individually.…
A Spectroscopic Survey of Field Red Horizontal-branch Stars
Casetti-Dinescu, Dana I.; Afşar, Melike; Sneden, Christopher +3 more
A metallicity, chemical composition, and kinematic survey has been conducted for a sample of 340 candidate field red horizontal-branch (RHB) stars. Spectra with high resolution and high signal-to-noise ratio were gathered with the McDonald Observatory 2.7 m Tull and the Hobby-Eberly Telescope echelle spectrographs, and were used to determine effec…
Spectroscopic Orbits for Late-type Stars. II
Abt, Helmut A.; Fekel, Francis C.; Willmarth, Daryl W. +1 more
We have determined spectroscopic orbital elements for 13 systems—10 single-lined binaries and three double-lined binaries. For the three binaries with previously published spectroscopic orbits, we have computed improved or comparable elements. While two systems have relatively short periods between 10 and 19 days, the remaining systems have much l…