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arXiv · 2604.20314

Shortest period for outer orbit in compact hierarchical triple? Discovery of SB1 around V0885 Per

Mikhail Kovalev
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Abstract

I present a discovery of SB1 in the LAMOST-MRS spectra of eclipsing contact binary V 885 Per. Spectroscopic orbit has period only $P=21.8$ day, which will make it shortest known outer period in compact hierarchical triple system, if this SB1 is indeed bound to the inner system. Unfortunately quality of available spectra don't allow to give definitive answer to this question, with other orbital hierarchy like 2+2 is also possible. Analysis of the eclipse timing variations showed a gradual increase in the orbital period of the inner eclipsing pair, as well as long-term changes that can be explained either by the light time travel effect due to an additional component or by magnetic activity.

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Mikhail Kovalev. 2026-04-22. Shortest period for outer orbit in compact hierarchical triple? Discovery of SB1 around V0885 Per. https://arxiv.org/abs/2604.20314

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