Cosmic Reionization On Computers: Statistics, Physical Properties and Environment of Lyman Limit Systems at $z\sim6$

Understand

Lyman limit systems (LLSs) are dense hydrogen clouds with high enough HI column densities to absorb Lyman continuum photons emitted from distant quasars.

• Their high column densities imply an origin in dense environments; however, the statistics and distribution of LLSs at high redshifts still remain uncertain.
• In this paper, we use self-consistent radiative transfer cosmological simulations from the "Cosmic Reionization On Computers" (CROC) project to study the physical properties of LLSs at the tail end of cosmic reionization at $z\sim6$.
• We generate 3000 synthetic quasar sightlines to obtain a large number of LLS samples in the simulations.