Deviations from hierarchical clustering in real and redshift space

Redshift-space distortions interfere with the estimation of high-order galaxy correlation functions. We find that deviations from hierarchical scaling of the galaxy distribution cannot be evaluated in redshift space. In addition, we show that an empirical technique, previously used to tentatively eliminate redshiftspace distortions and able to recover the correct behavior of the two-point function, heavily interferes with higher order function estimates. These conclusions are attained by analyzing both observational data (the Perseus-Pisces redshift survey [PPS]) and the results of 5123 cell particle-mesh simulations for cold dark matter and cold plus hot dark matter models. Using the neighbor-moment approach, we detect modest but significant deviations from hierarchical scaling in real space for simulated data. These are consistent with expectations for an initially biased galaxy field, once we take into account the displacements from the sites where galaxies formed due to observed nonlinear gravitational evolution. The passage to redshift space has the net effect of filtering out such distortions. Still on simulated data, taken in redshift space, we apply the empirical technique previously used on PPS data, aimed at reconstructing the real-space galaxy distribution. This technique is found to magnify the deviations from the hierarchical behavior of real-space data, if such deviations exist, and risks creating them artificially. Finally, the analysis of PPS data reveals a behavior similar to that seen in the simulations, both in redshift space and in reconstructed real space.