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arXiv · 2402.07045

Unraveling the Origins and Development of the Galactic Disk through Metal-Poor Stars

Maria Rah·Manolya Yatman·Ali Taani·Ahmad A. Abushattal·Mohammad K. Mardini
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Abstract

The Milky Way is a spiral galaxy comprising three main components: the Bulge, the Disk, and the Halo. Of particular interest is the Galactic disk, which holds a significant portion of the baryonic matter angular momentum and harbors at least two primary stellar populations: the thin and thick disks. Understanding the formation and evolution of the Galactic disk is crucial for comprehending the origins and development of our Galaxy. Stellar archaeology offers a means to probe the disk's evolution by listening to the cosmological narratives of its oldest and most pristine stars, specifically the metal-poor stars. In this study, we employed accurate photometric metallicity estimates and Gaia Early Data Release 3 astrometry to curate a pure sample of the oldest Galactic stars. This proceeding presents a summary of our primary findings.

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Maria Rah, Manolya Yatman, Ali Taani, Ahmad A. Abushattal, Mohammad K. Mardini. 2024-02-10. Unraveling the Origins and Development of the Galactic Disk through Metal-Poor Stars. https://arxiv.org/abs/2402.07045

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