Joint Astrophysical Colloquium
First stars and the 12C/13C isotopic ratio at the dawn of chemical evolution
David Aguado (Instituto de Astrofisica de Canarias)
Thursday 07/03/2024 @ 11:30, Sala Antonio Sollima (IV piano Battiferro)
During Big Bang Nucleosynthesis (BBN), hydrogen, helium, and small traces of lithium and beryllium were produced. A few million years after BBN, the first stars were formed out of this primordial material. Important questions about star formation, galactic evolution, and the yields of the first supernovae can be answered from the study of these first stars and their descendants. The most chemically primitive stars in the Milky Way are invaluable to understanding the early universe, but they are extremely rare and hard to find. We will review the main efforts in this regard and key results on the comprehensive study of these fossil records. The 12C/13C isotopic ratio is an important diagnostic tool in astrophysics, providing insights into the formation and evolution of stars and galaxies. We will focus on the information obtained from the oldest stars in the Milky Way, particularly the carbon-enhanced metal-poor (CEMP-no) stars. By analyzing the isotopic ratios in these stars, we can determine the changes in the ratio over time and how this has affected the overall composition of the Galaxy.