SO coloquio: The tidal arms of open star clusters are much longer than thought, but more difficult to find

The tidal arms of stellar clusters are an important tool for studying the clusters’ birth conditions, their evolution, coupling, and interaction with the Galactic potential. They also help understand how field stars populate the Milky Way. Thanks to Gaia, much progress has been accomplished in finding the tidal arms of open clusters. I will show here that such arms are much longer than previously observed, and that their identification requires not only a sophisticated analysis of the Gaia catalogue, using the convergent point method and clustering algorithms, but ideally, the use of N-body simulations and the new compact convergent point method. I will highlight recent results about the arms of several open clusters, which extend over several hundreds of parsecs.