Maximum-likelihood fitting of the 6dFGS peculiar velocities

Abstract

AbstractWe develop a robust Bayesian model to derive peculiar velocities and Fundamental Plane (FP) distances for a subsample of 9000 galaxies from the 6dF Galaxy Survey (6dFGS). These galaxies form the basis of 6dFGSv, the largest and most uniform galaxy peculiar-velocity sample to date. We perform a Bayesian analysis of the data set as a whole, determining cosmological parameters from the peculiar-velocity field (e.g., fitting β and the bulk flow), by comparing to the field predicted from the redshift survey and assuming that the galaxy distribution traces the matter distribution.