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The Third US Naval Observatory CCD Astrograph Catalog (UCAC3)
Zacharias, N.; Girard, T.; Makarov, V. +27 more
The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3, was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8-16 mag. Current epoch positions are obtained from the observat…
Spectroscopic Abundances and Membership in the Wolf 630 Moving Group
King, Jeremy R.; Bubar, Eric J.
The concept of kinematic assemblages evolving from dispersed stellar clusters has remained contentious since Eggen's initial formulation of moving groups in the 1960s. With high-quality parallaxes from the Hipparcos space astrometry mission, distance measurements for thousands of nearby, seemingly isolated stars are currently available. With these…
Proper-motion Study of the Magellanic Clouds Using SPM Material
Casetti-Dinescu, Dana I.; Girard, Terrence M.; Korchagin, Vladimir I. +8 more
Absolute proper motions are determined for stars and galaxies to V = 17.5 over a 450 deg2 area that encloses both Magellanic Clouds. The proper motions are based on photographic and CCD observations of the Yale/San Juan Southern Proper Motion program, which span a baseline of 40 years. Multiple, local relative proper-motion measures are…
Space Velocities of Southern Globular Clusters. VI. Nine Clusters in the Inner Milky Way
Casetti-Dinescu, Dana I.; Girard, Terrence M.; Korchagin, Vladimir I. +2 more
We have measured the absolute proper motions of nine low-latitude, inner Galaxy globular clusters, namely, NGC 6273 (M 19), NGC 6284, NGC 6287, NGC 6293, NGC 6333 (M 9), NGC 6342, NGC 6356, NGC 6388, and NGC 6441. These are the first determinations ever made for these clusters. The proper motions are on the International Celestial Reference System…
Discovery of a Faint Companion to Alcor Using MMT/AO 5 µm Imaging
Meyer, Michael R.; Kenworthy, Matthew A.; Mamajek, Eric E. +1 more
We report the detection of a faint stellar companion to the famous nearby A5V star Alcor (80 UMa). The companion has M-band (λ = 4.8 µm) magnitude 8.8 and projected separation 1.''11 (28 AU) from Alcor. The companion is most likely a low-mass (~0.3 M ⊙) active star which is responsible for Alcor's X-ray emission detected by ROSAT …
Orbit Determination of Double-lined Spectroscopic Binaries by Fitting the Revised Hipparcos Intermediate Astrometric Data
Ren, Shulin; Fu, Yanning
Untill now, the Hipparcos intermediate astrometric data (HIAD) have contributed little to the full orbit determination of double-lined spectroscopic binaries (SB2s). This is because the photocenter of such a binary system is usually not far from the system mass center, and its orbital wobble is generally weak with respect to the accuracy of the HI…
UCAC3 Proper Motion Survey. I. Discovery of New Proper Motion Stars in UCAC3 with 0farcs40 yr-1 > µ >= 0farcs18 yr-1 Between Declinations -90° and -47°
Henry, Todd J.; Finch, Charlie T.; Zacharias, Norbert
This paper presents 442 new proper motion stellar systems in the southern sky between declinations -90° and -47° with 0farcs40 yr-1 > µ >= 0farcs18 yr-1. These systems constitute a 25.3% increase in new systems for the same region of the sky covered by previous SuperCOSMOS RECONS (SCR) searches that used Schmidt p…
UCAC3: Astrometric Reductions
Finch, Charlie T.; Zacharias, Norbert; Wycoff, Gary L.
Presented here are the details of the astrometric reductions from the x, y data to mean right ascension (R.A.), declination (decl.) coordinates of the third U.S. Naval Observatory CCD Astrograph Catalog (UCAC3). For these new reductions we used over 216,000 CCD exposures. The Two-Micron All-Sky Survey (2MASS) data are used extensively to probe for…
New Precision Orbits of Bright Double-lined Spectroscopic Binaries. IV. 66 Andromedae, HR 6979, and HR 9059
Williamson, Michael H.; Fekel, Francis C.; Tomkin, Jocelyn
We have determined improved spectroscopic orbits for three double-lined binaries, 66 And (F4 V), HR 6979 (Am), and HR 9059 (F5 IV) using radial velocities from the 2.1 m telescope at McDonald Observatory, the coudé feed telescope at Kitt Peak National Observatory, and 2 m telescope at Fairborn Observatory. The orbital periods range from 11.0 to 14…
First Orbit Solutions and Calculated Masses of 10 Visual Binaries
Ling, J. F.
This paper presents the first reported orbits and masses of 10 visual double stars, all of which have described arcs of less than 180° since the first observation: WDS 00209+1059 (BU 1093), WDS 02405 - 2408 (SEE 19), WDS 05289 - 0318 (DA 6), WDS 07347+3852 (HU 842 AB), WDS 07546 - 0248 (STF 1157), WDS 08127+2613 (A 2471), WDS 08456+8442 (A 1078), …