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arXiv · 2407.21399

The Villafranca project: Combining Gaia and ground-based surveys to study Galactic OB groups

J. Maíz Apellániz·R. H. Barbá·J. A. Molina Lera·A. Lambarri Martínez·R. Fernández Aranda
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Abstract

The Villafranca project is studying Galactic stellar groups with OB stars combining information from $Gaia$ and ground-based surveys. We summarize the status of the project and we present its most important results. The Villafranca project has been used to produce a new astrometric calibration for $Gaia$ (E)DR3, which improves the previous one significantly for bright stars. We have discovered that dynamical interactions among massive stars at a very young age ($\sim$1 Ma or less) can play a significant interaction in the dynamical evolution of clusters. As a consequence, our current view of the massive-star IMF may be distorted and the number of free-floating neutron stars and black holes higher than previously considered.

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J. Maíz Apellániz, R. H. Barbá, J. A. Molina Lera, A. Lambarri Martínez, R. Fernández Aranda. 2024-07-31. The Villafranca project: Combining Gaia and ground-based surveys to study Galactic OB groups. https://arxiv.org/abs/2407.21399

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