The chemical evolution of the Universe is governed by the nucleosynthesis contribution from stars, which in turn is determined primarily by the initial stellar mass. I will review models of the slow neutron capture process (the s-process) and stellar yields from single metal-poor stars up to about 8 solar mass. Stars in this mass range evolve to become cool red giants after the main sequence....
In this talk, I will review the evolution of stars at low metallicity (Z) and in metal-free environments. I will focus on massive stars, rotation and mass loss and their dependence on metallicity. I will also review key uncertainties, both stellar and nuclear. Finally, I will present results on the (not always) weak s process in massive low-Z rotating stars.
GW170817/SSS17a was an event of the century that opened a new window to multi-messenger astronomy and astrophysics. Optical and near-infrared emissions among them suggest that their total energy release is consistent with radiative decays of theoretical prediction of r-process nuclei although no specific r-process element was identified. Core-collapse supernovae (both MHD Jet- and ν-SNe) are...
Ultra-faint dwarf galaxies are ideal systems to perform stellar
archaeology, as each galaxy provides multiple metal-poor stars sampling an
independent burst of star formation and chemical enrichment from the early
universe. In this talk, I will discuss the neutron-capture element
signature in ultra-faint dwarf galaxies, which chemically distinguish these
systems from most halo stars, globular...
The first stars in the universe must have provided chemical imprints on the surface of observed metal-poor stars with [Fe/H]<-2. One of the most important signatures is the abundances of carbon-enhanced metal-poor (CEMP) stars, which is defined as [C/Fe]>=0.7. The origin of a CEMP star and its subclasses such as CEMP-s and CEMP-no stars, divided by the enhancement of s-process elements,...
