Gaia Search for stellar Companions of TESS Objects of Interest III

TL;DR

This study uses Gaia data to identify and characterize stellar companions to TESS Objects of Interest, revealing 124 binary and 7 triple systems within 500pc, with detailed properties and distribution of these companions.

Contribution

It presents the largest Gaia-based survey of stellar multiplicity among TESS targets, identifying new companions and analyzing their properties and distribution.

Findings

124 binary and 7 triple systems detected

Companions mostly range from 0.09 to 2.5 solar masses

Companion frequency peaks at 500au separation

Abstract

The latest results from our ongoing multiplicity study of (Community) TESS Objects of Interest are presented, using astro- and photometric data from the ESA-Gaia mission, to detect stellar companions of these stars and characterize their properties. A total of 124 binary and 7 hierarchical triple star systems were detected among 2175 targets, whose multiplicity was investigated in the course of our survey, which are located at distances closer than about 500pc around the Sun. The detected companions and the targets are located at the same distance and share a common proper motion, as expected for components of gravitationally bound stellar systems, as proven with their accurate Gaia EDR3 astrometry. The companions have masses in the range between about 0.09 and 2.5$M_\odot$ and are most frequently found in the mass range between 0.15 and 0.8$M_\odot$. The companions exhibit projected separations to the targets between about 50 to 9700au and their frequency is the highest and constant up to about 500au, while it decreases for larger projected separations. In addition to mainly mid M to early K dwarfs, 4 white dwarf companions were detected in this survey, whose true nature could be identified with their photometric properties.