Forecasting [C ii] Line-intensity Mapping Measurements between the End of Reionization and the Epoch of Galaxy Assembly

Abstract

We combine recent simulation work on the SFR–[C ii ] correlation at high redshift with empirical modeling of the galaxy–halo connection (via UniverseMachine ) to forecast [C ii ] auto power spectra from z  ∼ 4 to z  ∼ 8. We compare these to sensitivities realistically expected from various instruments expected to come online in the next decade. If the predictions of our model are correct, [C ii ] should be detectable up to z  ∼ 6 in this generation of surveys, but detecting [C ii ] past the end of reionization will require a generational leap in line-intensity survey capabilities.