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[13.01] Cluster Masses Derived From X-ray and Sunyaev-Zel'dovich Effect Measurements

S. J. LaRoque (University of Chicago), M. Joy (NASA MSFC), M. Bonamente (University of Alabama, Huntsville), J. E. Carlstrom (University of Chicago), K. S. Dawson (U. C. Berkeley)

We infer the gas mass and total gravitational mass of 11 clusters using two different methods; analysis of X-ray data from the Chandra X-ray Observatory and analysis of centimeter-wave Sunyaev-Zel'dovich Effect (SZE) data from the BIMA and OVRO interferometers. This flux-limited sample of clusters from the BCS cluster catalogue was chosen so as to be well above the surface brightness limit of the ROSAT All Sky Survey; this is therefore an orientation unbiased sample. The gas mass fraction, f_g, is calculated for each cluster using both X-ray and SZE data, and the results are compared at a fiducial radius of r₅₀₀. Comparison of the X-ray and SZE results for this orientation unbiased sample allows us to constrain cluster systematics, such as clumping of the intracluster medium. We derive an upper limit on the matter density of the universe assuming that the mass composition of clusters within r₅₀₀ reflects the universal mass composition. We also demonstrate how the mean f_g derived from the sample can be used to estimate the masses of clusters discovered by upcoming deep SZE surveys.

Bulletin of the American Astronomical Society, 35#2
© 2003. The American Astronomical Soceity.