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arXiv · 2110.00243

The metal-poor end of the Spite plateau. II. Detailed chemical investigation

A. Matas Pinto·M. Spite·E. Caffau·P. Bonifacio·L. Sbordone·T. Sivarani·M. Steffen·F. Spite·P. Francois·P. Di Matteo
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Abstract

Context. The study of old, metal-poor stars deepens our knowledge on the early stages of the universe. In particular, the study of these stars gives us a valuable insight into the masses of the first massive stars and their emission of ionising photons. Aims. We present a detailed chemical analysis and determination of the kinematic and orbital properties of a sample of 11 dwarf stars. These are metal-poor stars, and a few of them present a low lithium content. We inspected whether the other elements also present anomalies. Methods. We analysed the high-resolution UVES spectra of a few metal-poor stars using the Turbospectrum code to synthesise spectral lines profiles. This allowed us to derive a detailed chemical analysis of Fe,

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A. Matas Pinto, M. Spite, E. Caffau, P. Bonifacio, L. Sbordone, T. Sivarani, M. Steffen, F. Spite, P. Francois, P. Di Matteo. 2021-10-01. The metal-poor end of the Spite plateau. II. Detailed chemical investigation. https://doi.org/10.1051/0004-6361%2F202141288

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