A New Method to Estimate Cosmological Parameters Using Baryon Fraction of Clusters of Galaxies

Abstract

We propose a new method to estimate cosmological parameters using the baryon fraction of clusters of galaxies for a range of redshifts. The basic assumption is that the baryon fraction of clusters is constant, which is a reasonable assumption when it is averaged within a Mpc scale. We find that the baryon fraction vs. redshift diagram can estimate the cosmological parameters, since the derived value of the baryon fraction from observations depends on the adopted value of cosmological parameters. We also discuss some points in comparing theoretical calculations with observations.

4 pages. LaTeX and 2 postscript figures. to appear in PASJ