Cluster-galaxy correlation functions in core normalized CDM models

We analyze the galaxy-galaxy and cluster-galaxy two-point correlation functions, xi(gg) and xi(cg), in open (Omega(0) = 0.4, Omega(Lambda) = 0, sigma(8) = 0.75, h(100) = 0.65), and flat (Omega(0) = 0.3, Omega(Lambda) = 0.7, sigma(8) = 1.05, h(100) = 0.65) CDM models which both reproduce the observed abundances of rich clusters of galaxies. We estimate xi(cg) for a sample taken from the APM cluster survey finding a power-law fit xi(cg) = (r/r0)(gamma) with r(0) = 10.0 +/- 0.7 h(-1) Mpc and gamma similar or equal to -2.1. For the open and flat-antibiased CDM models explored we find the corresponding cluster-galaxy correlation lengths 6.5 +/- 0.7 h(-1) Mpc and 7.2 +/- 0.5 h(-1) Mpc respectively, significantly lower than the observed value. Our results indicate that COBE-normalized CDM models are not able to reproduce the spatial cross-correlation of clusters and galaxies.