“CARACTERIZANDO ESTRELAS GIGANTES VERMELHAS NO AGLOMERADO ABERTO IC 2714: UM ESTUDO ECTROSCÓPICO E ASTROMÉTRICO”

Abstract

In this work, our objective is to conduct a comprehensive study of a sample of eight red giants previously reported as members of the open cluster IC 2714. Using high-resolution spectra, we have performed a chemical analysis by determining atmospheric parameters, projected rotational velocities, and chemical abundances for 21 species in the sample, employing equivalent width measurements and spectral synthesis as techniques. Further- more, using robust algorithms from recent literature, we have conducted a membership study using astrometric data and estimated the physical parameters of the cluster through isochrone fitting. Our astrometric study allows us to classify 898 stars as cluster members, and due to their discrepant astrometric results, two stars in our sample were classified as non-members. The chemical abundances of all the red giants classified as members in our sample agree with literature results for dwarfs and giants in the solar neighbor- hood. Moreover, three stars in our sample exhibit anomalous rotation, and among them, we report a lithium-rich giant candidate. To explain this chemically peculiar nature, we suggest that this star underwent accretion of a planet or substellar companion, which possibly triggered a self-enrichment lithium process. Finally, we discuss our results for the open cluster IC 2714 in the context of chemical gradients in the Galaxy and the study of cosmic chronometers. The results of this work can contribute to the study of stellar nucleosynthesis models and Galactic chemical evolution models, in addition to guiding possible more in-depth studies.