Title: Galactic archaeology with the rarest fossils
Speaker: Thomas Nordlander
Affiliation: Australian National University
Time: Monday 30 May 2022, 1400 to 1500
Location: 90102Å and also online at https://uu-se.zoom.us/j/62091586806
Abstract:
The oldest stars in our Galaxy are a fossil record of the very first generation of stars. Their chemical makeup carries clues to the properties of these first stars, in particular their masses and properties of their supernovae. The field has made great progress in the "stamp collection" stage, where a small number of the oldest (most iron-poor) stars known can be directly mapped to individual supernovae in the early Universe. The interpretation obviously requires accurately estimated chemical abundances, through advanced spectroscopic modelling. But even aside from this, the mapping of chemical abundances to supernova properties is not as obvious as it seems. Gathering a more complete picture requires moving beyond stamp collection into a holistic understanding of how the IMF couples with explosion properties and the injection of metals into the interstellar medium to form the second generation of stars. I will discuss these pitfalls, and outline suggestions that enable putting real constraints on the initial mass function of the first stars.