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arXiv · 2202.07942

Astrometric star-cluster membership probability: application to the case of M 37 with Gaia EDR3

M. Griggio·L. R. Bedin
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Abstract

In this work, starting from the well-accepted relations in literature, we introduce a new formalism to compute the astrometric membership probabilities for sources in star clusters, and we provide an application to the case of the open cluster M 37. The novelty of our approach is a refined -- and magnitude-dependent -- modelling of the parallax distribution of the field stars. We employ the here-derived list of members to estimate the cluster's mean systemic astrometric parameters, which are based on the most recent Gaia's catalog (EDR3).

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M. Griggio, L. R. Bedin. 2022-02-16. Astrometric star-cluster membership probability: application to the case of M 37 with Gaia EDR3. https://doi.org/10.1093/mnras%2Fstac391

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