Gaia Search for stellar Companions of TESS Objects of Interest II

TL;DR

This study uses Gaia data to identify and characterize stellar companions of TESS Objects of Interest, revealing multiple binary and multiple star systems within 500 parsecs, including white dwarfs, with detailed properties and separation distributions.

Contribution

It provides the first comprehensive Gaia-based survey of stellar companions to TESS targets, including new detections and characterization of their properties and distributions.

Findings

113 binary systems detected among 585 targets

Companions range from 0.09 to 4.5 solar masses

Companion separation ranges from 120 to 9500 AU

Abstract

We present the latest results of our ongoing multiplicity study of (Community) TESS Objects of Interest, using astro- and photometric data from the ESA-Gaia mission, to detect stellar companions of these stars and to characterize their properties. In total, 113 binary, 5 hierarchical triple star systems, as well as one quadruple system were detected among 585 targets surveyed, which are all located at distances closer than about 500pc around the Sun. As proven with their accurate Gaia EDR3 astrometry the companions and the targets are located at the same distance and share a common proper motion, as it is expected for components of gravitationally bound stellar systems. The companions exhibit masses in the range between about 0.09$M_\odot$ and 4.5$M_\odot$ and are most frequently found in the mass range between 0.15 and 0.6$M_{\odot}$. The companions are separated from the targets by about 120 up to 9500au and their frequency is the highest and constant within about 500au while it continually decreases for larger separations. Beside mainly early to mid M dwarfs, also 5 white dwarf companions were identified in this survey, whose true nature was revealed by their photometric properties.