Speaker
Description
Runaway stars are thought to have been ejected from star clusters with high velocities relative to the cluster centre-of-mass motion. There are two competing mechanisms for their production: supernova-based ejections in binaries, where one companion explodes leaving no remnant and launching the other companion at the instantaneous orbital velocity, and the disintegration of triples (or higher-order multiples) producing a recoiled runaway binary (RB) and a runaway star (RS).
After discussing the theoretical expectations for both mechanisms, we search for runaway star candidates using data from the Gaia DR3 survey, with a focus on triple disintegration in the old open cluster M67. We create a systematic methodology to look for candidate RS/RB runaway pairs produced from the disintegration of bound three-body systems formed from single-binary interactions, based on momentum conservation and causality. The method is general, and can be applied to any cluster having a 5D kinematic data set. We use our criteria to search for these pairs in a 150 pc circular field of view surrounding the open cluster M67, which we use as a benchmark cluster to test the robustness of our method. Our results reveal only one RS/RB pair that is consistent with all of our selection criteria, out of an initial sample size of $\sim$ 10$^{8}$ pairs (i.e., $\sim$ 10$^{4}$ objects).
| Affliation | Universidad de Concepción |
|---|---|
| Current Position | Masters or undergraduate student |
