Characterization of the Visual Binary TOI-6883AB and its dynamical implications for the planetary companion TOI-6883Ab

TL;DR

This study confirms TOI-6883 as a binary star system and examines how its stellar companion influences the stability and dynamics of its orbiting exoplanet, TOI-6883Ab.

Contribution

It provides the first detailed characterization of the binary nature of TOI-6883 and assesses the dynamical implications for its planetary companion.

Findings

TOI-6883 is a physically bound binary system with a separation of 616 AU.

The planetary orbit is stable over long timescales despite potential Kozai-Lidov effects.

The system's orbital period is estimated at approximately 15,000 years.

Abstract

We demonstrate that TOI-6883 is a physically bound visual binary system composed of two solar-type stars, TOI-6883A (TIC 393818343) and TOI-6883B (TIC 393818340), initially regarded as a single star hosting the exoplanet TOI-6883b. Gaia DR3 astrometry shows that both stars have nearly identical parallaxes 10.6 mas, consistent proper motions, and a projected separation of 616 AU, confirming their binary nature. Using astrometric and photometric data, we estimate the stellar masses, physical separation, and an orbital period of 15,000 years. The system is energetically bound. We revise the planet designation to TOI-6883Ab to reflect stellar multiplicity. We evaluate the impact of the binary companion on planetary stability and find the planet's orbit to be long-term stable, although Kozai-Lidov perturbations remain possible. Further astrometric and photometric follow-up will be essential to better constrain the binary orbit and assess potential dynamical influences on the planetary architecture.