Speaker
Description
JWST has opened a new chapter in our understanding of early star formation, unveiling a surprising number of luminous galaxies at z>10, as well as the first quenched low-mass galaxies. This coexistence of extreme sources, exhibiting a wide range of star formation rates, suggests a highly stochastic evolution and raises fundamental questions. Are galaxies more bursty at high-z and why? How does this affect our view of the high-z Universe?
Using a simple analytical approach, we show that due to bursty time-variable star formation histories (SFH), dark matter haloes of mass Mh can host galaxies with a broad range of luminosities. Specifically, introducing a scatter in the UV magnitudes that increases with decreasing Mh can naturally explain the observed luminosity functions up to z~12.
I will show how bursty SFHs are expected to affect the distributions of other key observables, such as UV slopes, emission lines and neutral hydrogen fractions. These predictions will help us constrain the stochasticity in high-z galaxies and unveil the physical processes regulating their evolution.
