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arXiv · 1512.04991

WIYN Open Cluster Study. XXXVI. Spectroscopic Binary Orbits in NGC 188

Aaron M. Geller·Robert D. Mathieu·Hugh C. Harris·Robert D. McClure
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Abstract

We present 98 spectroscopic binary orbits resulting from our ongoing radial-velocity survey of the old (7 Gyr) open cluster NGC 188. All but 13 are high-probability cluster members based on both radial-velocity and proper-motion membership analyses. Fifteen of these member binaries are double lined. Our stellar sample spans a magnitude range of 10.8 <=V<= 16.5 (1.14-0.92 Msun) and extends spatially to 17 pc (~13 core radii). All of our binary orbits have periods ranging from a few days to on the order of 10^3 days, and thus are hard binaries that dynamically power the cluster. For each binary, we present the orbital solutions and place constraints on the component masses. Additionally, we discuss a few binaries of note from our sample, identifying a likely blue straggler-blue straggler binary system (7782), a double-lined binary with a secondary star which is under-luminous for its mass (5080), two potential eclipsing binaries (4705 and 5762), and two binaries which are likely members of a quadruple system (5015a and 5015b).

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Aaron M. Geller, Robert D. Mathieu, Hugh C. Harris, Robert D. McClure. 2015-12-15. WIYN Open Cluster Study. XXXVI. Spectroscopic Binary Orbits in NGC 188. https://doi.org/10.1088/0004-6256%2F137%2F4%2F3743

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