Independent measurements of the dynamical masses of six galaxy clusters in the local universe.
Abstract (from CDS):
We present independent measurements of the masses of galaxy clusters in the local universe by employing the Dynamical Mass Estimator (DME) originally developed by Falco et al. In the catalog of the galaxy groups/clusters constructed by Tempel et al. from Sloan Digital Sky Survey Data Release 10, we search for galaxy clusters as the targets around which neighbor galaxies constitute thin straight filamentary structures in the configuration space spanned by the redshifts and the projected distances. Out of the 29 Sloan clusters that have 100 or more member galaxies, a total of six targets are found to have filamentary structures in their bound zones. For each of the six targets, we construct the profile of the recession velocities of the filament galaxies, which depend on the cluster mass and the angle of the filament relative to the line-of-sight direction. Fitting the constructed profile to the universal formula with constant amplitude and slope, we statistically determine the dynamical mass of each cluster and compare it with previous estimates made using the conventional method. The weak and strong points of the DME, as well as its prospects for measuring the dynamical masses of high-z clusters, are discussed.