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Eclipsing Binary Solutions in Physical Units and Direct Distance Estimation
Wilson, R. E.
Opportunities for extraction of distances and temperatures from eclipsing binary light curves that are in standard flux units, as opposed to traditional arbitrary units, are examined. Benefits include (1) distance becomes an ordinary solution parameter with a standard error, (2) temperatures of both stars may be derivable in favorable circumstance…
CHARA Array Measurements of the Angular Diameters of Exoplanet Host Stars
Goldfinger, P. J.; McAlister, Harold A.; ten Brummelaar, Theo A. +5 more
We have measured the angular diameters for a sample of 24 exoplanet host stars using Georgia State University's CHARA Array interferometer. We use these improved angular diameters together with Hipparcos parallax measurements to derive linear radii and to estimate the stars' evolutionary states.
Identifying Stellar Streams in the First RAVE Public Data Release
Rix, H. -W.; Klement, R.; Fuchs, B.
We have searched for and detected stellar streams or moving groups in the solar neighborhood, using the data provided by the first RAVE public data release. This analysis is based on distances to RAVE stars estimated from a color-magnitude relation calibrated on Hipparcos stars. Our final sample consists of 7015 stars selected to be within 500 pc …
A Study of the ρ Ophiuchi Cloud: Mapping the Distribution and the Motions of Interstellar Gas
Welty, Daniel E.; Snow, Theodore P.; Destree, Joshua D.
Guest Investigator results from Hipparcos, combined with high-resolution optical spectra obtained with the Anglo-Australian Observatory, Kitt Peak National Observatory, and McDonald Observatory, are used to create a three-dimensional map of the stars and several interstellar gas components in the ρ Oph cloud complex. Many principal gas components …
Tomographic Separation of Composite Spectra. XI. The Physical Properties of the Massive Close Binary HD 100213 (TU Muscae)
Gies, Douglas R.; Penny, Laura R.; Ouzts, Cynthia
We present the results of a Doppler tomographic reconstruction of the UV spectra of the double-lined, O binary HD 100213 based on observations made with the International Ultraviolet Explorer (IUE). We used cross-correlation methods to obtain radial velocities, confirm the orbital elements, estimate the UV flux ratio, and determine projected rotat…
Interferometric Studies of the Extreme Binary epsilon Aurigae: Pre-Eclipse Observations
Stencel, Robert E.; Creech-Eakman, Michelle; Hart, Alexa +3 more
We report new and archival K-band interferometric uniform disk diameters obtained with the Palomar Testbed Interferometer for the eclipsing binary star epsilon Aurigae, in advance of the start of its eclipse in 2009. The observations were intended to test whether low-amplitude variations in the system are connected with the F supergiant star (prim…
Synthetic Spectrum Constraints on a Model of the Cataclysmic Variable QU Carinae
Szkody, Paula; Sion, Edward M.; Godon, Patrick +3 more
Neither standard model SEDs nor truncated standard model SEDs fit observed spectra of QU Carinae with acceptable accuracy over the range 900-3000 Å. Nonstandard model SEDs fit the observation set accurately. The nonstandard accretion disk models have a hot region extending from the white dwarf to R = 1.36RWD, a narrow intermediate-tempe…
A New Orbit Determination for Bright Sungrazing Comet of 1843
Sekanina, Zdenek; Chodas, Paul W.
Given the critical role of the bright sungrazer C/1843 D1, also called the Great March Comet of 1843, in hypotheses of the origin and evolution of the Kreutz system, a new orbital investigation of this comet was desirable. Closely inspecting Kreutz's classical work, we conclude that his result of 512 yr for the orbital period, which has been endle…
On the Formation of Perseus OB1 at High Galactic Latitudes
Lim, Jeremy; Lee, Hsu-Tai
The Per OB1 association, which contains the remarkable double cluster h and χ Per, is unusual in not having a giant molecular cloud in its vicinity. We show from Hipparcos data that the luminous members of this association exhibit a bulk motion away from the Galactic plane, such that their average velocity increases with height above the Galactic …
Measuring Stellar Radial Velocities with a Dispersed Fixed-Delay Interferometer
Ge, Jian; Mahadevan, Suvrath; Fleming, Scott W. +5 more
We demonstrate the ability to measure precise stellar barycentric radial velocities with the dispersed fixed-delay interferometer technique using the Exoplanet Tracker (ET), an instrument primarily designed for precision differential Doppler velocity measurements using this technique. Our barycentric radial velocities, derived from observations ta…