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arXiv · 2110.03837

Reconstructing the Pleiades with Gaia EDR3

Jeremy Heyl·Ilaria Caiazzo·Harvey Richer
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Abstract

We search through an eight-million cubic-parsec volume surrounding the Pleiades star cluster and the Sun to identify both the current and past members of the Pleiades cluster within the Gaia EDR3 dataset. We find nearly 1,300 current cluster members and 289 former cluster candidates. Many of these candidates lie well in front or behind the cluster from our point of view, so formerly they were considered cluster members, but their parallaxes put them more than 10 pc from the centre of the cluster today. Over the past 100 Myr we estimate that the cluster has lost twenty percent of its mass including two massive white dwarf stars and the $α^2$ Canum Venaticorum-type variable star, 41 Tau. All three white dwarfs associated with the cluster are massive ($1.01-1.06~\textrm{M}_\odot$) and have progenitors with main-sequence masses of about six solar masses. Although we did not associate any giant stars with the cluster, the cooling time of the oldest white dwarf of 60~Myr gives a firm lower limit on the age of the cluster.

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Jeremy Heyl, Ilaria Caiazzo, Harvey Richer. 2021-10-08. Reconstructing the Pleiades with Gaia EDR3. https://doi.org/10.3847/1538-4357%2Fac45fc

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