Title:

Galactic Evolutionary Path From Primeval Irregulars 
To Present-Day Ellipticals



Masao Mori
UCLA



Abstract:

The current understanding of galaxy formation is that it
proceeds in a 'bottom up' way, with the formation of small
clumps of gas and stars that merge hierarchically until
giant galaxies are built up. The baryonic gas loses the
thermal energy by radiative cooling and falls towards the
centres of the new galaxies, while supernovae blow gas
out. Any realistic model therefore requires a proper
treatment of these processes, but hitherto this has been far
from satisfactory. Here I report an ultra-high-resolution
simulation that follows evolution from the earliest stages
of galaxy formation through the period of dynamical
relaxation. The bubble structures of gas revealed in our
simulation (<3 x 10^8 years) resemble closely the
high-redshift Lyman α emitters. After 10^9 years these
bodies are dominated by stellar continuum radiation and look
like the Lyman break galaxies known as the high-redshift
star-forming galaxies at which point the abundance of heavy
elements appears to be solar. After 1.3 x 10^10 years, these
galaxies resemble present-day ellipticals.