Harvard University Department of Astronomy

The Cosmological Constant Cluster Baryon Fraction Basic Idea: Know number of baryons from big bang nucleosynthesis, and estimate limit on their fraction from galaxy clusters to get upper mass limit. "Cluster baryon catastrophe." Systems of interest: Galaxy clusters discussed in structure formation section Observations Assumptions: "fair sample", equilibrium, smooth, all baryons in gas Current Results Caveats and criticisms Some References Home Syllabus References Lecture References Useful Links Contact Info