High-order correlations of peaks and halos: A step toward understanding galaxy biasing

We develop an analytic model for the hierarchical correlation amplitudesS_j_,_g(R)#ident to# anti #xi#_j_,_g(R) anti #xi#_2_,_g"j"-"1(R) [where j=3, 4, 5, and anti #xi#_j_,_g(R) is the jth order connected moment of counts in spheres of radius R] of density peaks and dark matter halos in the quasi-linear regime. The statistical distributions of density peaks and dark matter halos within the initial density field (assumed Gaussian) are determined by the peak formalism of Bardeen et al. (1986) and by an extension of the Press-Schechter formalism, respectively. Modifications of these distributions caused by gravitationally induced motions are treated using a spherical collapse model. We test our model against results for S_3_,_g(R) and S_4_,_g(R) from a variety of N-body simulations. The model works well for peaks even on scales where the second moment of mass (anti #xi#_2) is significantly greater than unity. The model also works successfully for halos that are identified earlier than the time when the moments are calculated. Because halos are spatially exclusive at the time of their identification, our model is only qualitatively correct for halos identified at the same time as the moments are calculated45 refs.Available from TIB Hannover: RR 4697(938) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman