Stars, Interstellar Medium and the Galaxy Commons^™

Hydrostatic And Caustic Mass Profiles Of Galaxy Clusters, Ben J. Maughan, Paul A. Giles, Kenneth J. Rines, Antonaldo Diaferio, Margaret J. Geller, Nina Van Der Pyl, Massimiliano Bonamente

Physics & Astronomy

We compare X-ray and caustic mass profiles for a sample of 16 massive galaxy clusters. We assume hydrostatic equilibrium in interpreting the X-ray data, and use large samples of cluster members with redshifts as a basis for applying the caustic technique. The hydrostatic and caustic masses agree to better than ≈20 per cent on average across the radial range covered by both techniques (∼[0.2–1.25]R₅₀₀). The mass profiles were measured independently and do not assume a common functional form. Previous studies suggest that, at R₅₀₀ , the hydrostatic and caustic masses are biased low and high, respectively. …