Angular and three--dimensional correlation functions, determined from the Muenster Red Sky Survey

Abstract

We measured the two dimensional galaxy--galaxy correlation function from the Muenster Red Sky Survey (Ungruhe 1999). This survey has a slightly larger surface as the APM survey and complete up to r_F<18.3 mag (z_{med} \sim 0.14). The large dynamical range of the survey made it possible to examine sub-catalogues with different limiting magnitudes. The positive part of our measured angular correlation functions (after the colour correction) agree excellently with those measured by Maddox, Efstathiou and Shutherland 1996 from the APM galaxy catalogue (Maddox et al. 1990). From the measured angular correlation functions the three dimensional two-point correlation function \xi(r) was calculated. We have chosen the evolution parameter \epsilon so that the change of the correlation length r_0 with the depth of the sub-catalogue were minimal. This prescription gives r_0 = 5.82 \pm 0.05 h^{-1} Mpc and a high, positive evolution parameter \epsilon = 2.6. We have estimated the average inflow/outflow velocity, corresponding to the evolution of the 3d correlation function. The position of the point, where the 3d correlation function breaks away from the power law depends on the depth of the sub-catalogues: for low magnitude limits the break-down comes earlier, for higher later.