Search Publications
The Radial Velocity Experiment (RAVE): Second Data Release
Gilmore, G.; Freeman, K. C.; Evans, N. W. +51 more
We present the second data release of the Radial Velocity Experiment (RAVE), an ambitious spectroscopic survey to measure radial velocities and stellar atmosphere parameters (temperature, metallicity, surface gravity, and rotational velocity) of up to one million stars using the 6 dF multi-object spectrograph on the 1.2 m UK Schmidt Telescope of t…
Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity
Latham, David W.; Stefanik, Robert P.; Massarotti, Alessandro +1 more
We present rotational and radial velocities for a sample of 761 giants selected from the Hipparcos Catalogue to lie within 100 pc of the Sun. Our original goal was to examine stellar rotation in field giants using spectroscopic line broadening to look for evidence of excess rotation that could be attributed to planets that were engulfed as the par…
A New VLA-Hipparcos Distance to Betelgeuse and its Implications
Harper, Graham M.; Brown, Alexander; Guinan, Edward F.
The distance to the M supergiant Betelgeuse is poorly known, with the Hipparcos parallax having a significant uncertainty. For detailed numerical studies of M supergiant atmospheres and winds, accurate distances are a prerequisite to obtaining reliable estimates for many stellar parameters. New high spatial resolution, multiwavelength, NRAO3<…
Open Clusters as Galactic Disk Tracers. I. Project Motivation, Cluster Membership, and Bulk Three-Dimensional Kinematics
Majewski, Steven R.; Frinchaboy, Peter M.
We have begun a survey of the chemical and dynamical properties of the Milky Way disk as traced by open star clusters. In this first contribution, the general goals of our survey are outlined and the strengths and limitations of using star clusters as a Galactic disk tracer sample are discussed. We also present medium-resolution (R ~ 15, 0000) spe…
Charge-Coupled Device Speckle Observations of Binary Stars with the WIYN Telescope. V. Measures During 2001-2006
Horch, Elliott P.; van Altena, William F.; Cyr, William M., Jr. +3 more
A total of 1067 speckle observations of 345 binary stars are presented. Of these, 161 are double stars first resolved by Hipparcos, 17 are resolved for the first time in the observations presented here, and 21 are stars previously discovered by our program and reported in earlier papers in the series. In 947 cases, a magnitude difference is report…
Main-Sequence Fitting Distance to the σ Ori Cluster
Walter, F. M.; Wolk, S. J.; Sherry, W. H. +1 more
The σ Ori cluster is an unbound aggregate of a few hundred young, low-mass stars centered on the multiple system σ Ori. This cluster is of great interest because it is at an age when roughly half of the stars have lost their protoplanetary disks, and the cluster has a very large population of brown dwarfs. One of the largest sources of uncertainty…
Direct Detection of the Close Companion of Polaris with the Hubble Space Telescope
Schaefer, Gail H.; Bond, Howard E.; Evans, Nancy Remage +5 more
Polaris, the nearest and brightest classical Cepheid, is a single-lined spectroscopic binary with an orbital period of 30 yr. Using the High Resolution Channel of the Advanced Camera for Surveys on board the Hubble Space Telescope (HST) at a wavelength of ~2255 Å, we have directly detected the faint companion at a separation of 0farcs17. A second …
Preliminary Orbit and Differential Photometry of the Nearby Flare Star CR Dra
Docobo, José A.; Tamazian, Vakhtang S.; Melikian, Norair D. +3 more
New speckle measurements with the 6 m telescope of the Special Astrophysical Observatory (Russia) and the first preliminary orbit of the nearby flare star CR Dra (=Gl 616.2; WDS 16171+5516; BLA 3) with a period of 4.04 yr and a semimajor axis of 0farcs148 are reported. The Hipparcos parallax of 48.36 ± 1.16 mas (distance 20.7 pc) leads to an unusu…
Tests of Broadband Photometric Consistency for Standard Stars, the Hyades, and M67
Joner, Michael D.; van Wyk, Francois; Taylor, Benjamin J. +1 more
New South African Astronomical Observatory (SAAO) BV(RI)C measurements of 19 Hyades stars and 11 M67 stars are reported. The zero points of the new color indices conform closely to those of SAAO data reported in a previous paper. In addition, the new M67 measurements of (V - R)C and (R - I)C are compared to data pu…
First Orbits for Five Binaries
Cvetković, Z.
In this paper, new orbital elements are given for five binaries. For all of them—Washington Double Star (WDS) 00469+4339 = HDS 102, WDS 02186+4017 = EGG 2Aa, WDS 05542 - 2909 = FIN 382, WDS 06493- 0216 = FIN 322, and WDS 11495 - 4604 = FIN 366—the orbital elements are calculated for the first time. One of the five binaries, HDS 102, was discovered…