ESO Santiago, Chile. August 3-4, 2023.

The principles of single and binary star evolution are generally accepted, but stars often form in triples or higher-order multiples, and the long-term evolution of these systems is poorly understood. The presence of a third star orbiting a binary system can significantly affect the evolution of the binary components, as well as drastically altering the evolution of the orbital parameters of the system. For example, dynamical interactions in three-body systems can lead to cycles of periodic variations of the eccentricity of the inner orbit and the mutual inclination between the two orbits. Additionally, the presence of the third star can enhance tidal effects in the binary and lead to interactions such as mass transfer and collisions.

The purpose of this meeting is to gather experts on multiple-star systems from all over Chile, with the goal of exchanging recent results and facilitating discussions about triples and higher-order multiplicity. We envision this meeting to be a fruitful and discussion-oriented in-person meeting where theorists and observers at different career stages exchange ideas. During this 2-day workshop, we hope to reach a global improvement of everyone's understanding of hierarchical multiple systems and trigger new collaborations and joint observing proposals.