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arXiv · 2607.09272

Structure of the Stellar Neighborhood of CQ Tau in the Presence of a Companion in an Elongated Orbit

Tatiana Demidova
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Abstract

There are indirect signs of the presence of a companion near the star CQ\,Tau. A period of 10\;years was found in the brightness changes. The image of the disk shows an extensive cavity with a size of about 25~AU, surrounded by a dust ring with a distribution maximum near 53~AU. A simulation of the interaction of dust and gas in the vicinity of the star with the CQ\,Tau parameters was carried out, assuming the existence of a companion in an orbit with a period of 10\;years. It was shown that an M-class star in a highly elongated orbit is capable of forming a region of reduced density around the center of mass of the system, with a size close to the observed one. However, the dust ring-like structure in this case is located noticeably closer to the star than observed. Evidence has been obtained that a massive planet in an outer, relatively binary orbit, could form a ring-shaped dust structure at a distance similar to that observed.

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Tatiana Demidova. 2026-07-10. Structure of the Stellar Neighborhood of CQ Tau in the Presence of a Companion in an Elongated Orbit. https://doi.org/10.1134/s1990341325600085

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