Physical Processes Commons^™

The Infall Region Of Abell 576: Independent Mass And Light Profiles, Kenneth Rines, Margaret J. Geller, Antonaldo Diaferio, Joseph J. Mohr, Gary A. Wegner

Dartmouth Scholarship

We describe observations of the nearby (cz = 11,487 km s^-1) cluster of galaxies Abell 576 beyond the virial radius and into the infall region where galaxies are on their first or second pass through the cluster. Using 1057 redshifts, we use the infall pattern in redshift space to determine the mass profile of A576 to a radius of ~4 h^-1 Mpc. This mass estimation technique makes no assumptions about the equilibrium state of the cluster. Within ~1 h^-1 Mpc, the mass profile we derive exceeds that determined from X-ray observations by a factor of …