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arXiv · 2306.02452

Gaia Search for stellar Companions of TESS Objects of Interest IV

M. Mugrauer·J. Rück·K. -U. Michel
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Abstract

We present the latest results of our ongoing multiplicity study of (Community) TESS Objects of Interest, using astrometric and photometric data from the ESA-Gaia mission to detect stellar companions of these stars and characterize their properties.\linebreak A total of 134 binary, 6 hierarchical triple, and two quadruple star systems are identified among 1106 targets whose multiplicity is investigated in the course of our survey, located at distances closer than about 500pc around the Sun. The detected companions and targets are at the same distance and have a common proper motion, as expected for components of gravitationally bound stellar systems, as demonstrated by their accurate Gaia DR3 astrometry. The companions have masses from about 0.11 to 2$M_\odot$ and are most abundant in the mass range between 0.2 and 0.5$M_\odot$. The companions have projected separations from the targets between about 50 and 9700au. Their frequency is the highest and constant from about 300 up to 750au, decreasing at larger projected separations. In addition to main sequence stars, four white dwarf companions are detected in this study, whose true nature is revealed by their photometric properties.

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M. Mugrauer, J. Rück, K. -U. Michel. 2023-06-04. Gaia Search for stellar Companions of TESS Objects of Interest IV. https://arxiv.org/abs/2306.02452

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