CAREER: Numerical Simulations of Reionization

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

AST- 0134373 Nickolay Gnedin Proposal ID: AST 0134373 Institution: University of Colorado at Boulder PI: Nickolay Gnedin Dr. Gnedin is awarded funds at the University of Colorado at Boulder to further develop new methods of modeling the first reionization of the early universe. Current data on the cosmic background radiation indicate that the gas content of the universe remained mostly neutral from the time of recombination at a redshift of about 1000 to a time corresponding to a redshift of about twenty. Observations of quasars at redshifts of about six indicated that, at that time, the intergalactic medium was highly ionized. Thus this "reionization", the shift of intergalactic gas from mostly neutral to mostly ionized, must have happened sometime between the times corresponding to redshifts of six and twenty. Dr. Gnedin will make significant improvements on numerical methods of modeling radiative transfer with the hope of achieving numerical convergence. These models will be able to make quantitatively accurate predictions for the evolution of the intergalactic medium for the first time. Dr. Gnedin will further compare the model results to "Lyman Break Galaxies," some of the most primordial observed galaxies, in an attempt to understand their formation. Dr. Gnedin will integrate his teaching and research by developing a new undergraduate course in cosmology for non-science majors, and developing the cosmology portion of a web-based course in general introductory astronomy. The web-based work will include original simulations drawn from his research. He will also work with undergraduate majors to develop a new planetarium show on cosmology.