Spectroscopic Orbits of Subsystems in Multiple Stars. XI

Andrei Tokovinin

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arXiv · 2507.07233

Spectroscopic Orbits of Subsystems in Multiple Stars. XI

Andrei Tokovinin

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Abstract

Adding to the large radial velocity survey of nearby solar-type stars (summary in Tokovinin, 2023a), spectroscopic orbits are determined for four hierarchical systems: HIP 49442 (inner and outer periods of 164.55 d and 34 yr, respectively), HIP 55691 (2.4 and 415 yr), HIP 61465 (86.8 d), and HIP 78662C (0.82 d). Each system is discussed individually. Seven Gaia orbits of low-mass dwarfs, each with two additional resolved (interferometric and wide) companions, i.e. potential quadruples, are tested by monitoring radial velocities; five orbits are confirmed and two are refuted. Five of these systems are quadruples of 3+1 hierarchy, one is quintuple, and one is triple. Strengths and limitations of the Gaia data on multiple systems and the need of complementary observations are highlighted.

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Andrei Tokovinin. 2025-07-09. Spectroscopic Orbits of Subsystems in Multiple Stars. XI. https://arxiv.org/abs/2507.07233

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