This is a talk given at lunch time, usually in the conference room at noon.
Supernovae (SNe) drive metal-enriched, galaxy-wide outflows. How the outflows impact the circumgalactic medium (CGM) depends on (a) how much mass/energy/metals the outflows carry, and (b) what is already in the CGM.
It is tempting to assert that the most metal-poor stars in the Galaxy are the direct descendants of the first stars. This is not necessarily the case though, as metal-poor stars form over a range of redshift.