A morphological, kinematical and chemical analysis of the disrupting open cluster UBC274

23 Nov 2023, 10:05
25m
Villa Galileo

Villa Galileo

Via del Pian dei Giullari, 42 Firenze
Session 5 Cluster Survival

Speaker

Laia Casamiquela (GEPI Observatoire de Paris)

Description

The wealth and homogeneity of Gaia data have allowed the discovery of several open clusters with signs of disruption.
We do a morphological, kinematic and chemical analysis of the disrupting cluster UBC 274 (2.5 Gyr, d = 1778 pc), with the objective of studying its global properties.
A new membership study up to 50 pc from its center and un to magnitude G=19 using GaiaEDR3 data, shows that the cluster has a highly eccentric (0.93) component, tilted  10 deg with respect to the plane of the Galaxy, which is morphologically compatible with the result of a test-particle simulation of a disrupting cluster.
We find a significant sign of mass segregation where the most massive stars appear 1.5 times more concentrated than other stars.
We obtained high resolution and high signal-to-noise spectra of 6 giants and subgiants. Our abundance analysis shows that the cluster has a slightly subsolar metallicity of [Fe=H] = -0.08\pm0.02. Its chemical pattern is compatible with that of Ruprecht 147, of similar age but located closer to the Sun, with the remarkable exception of neutron-capture elements which present an overabundance.

Primary author

Laia Casamiquela (GEPI Observatoire de Paris)

Presentation materials