Scaling of the 1-halo terms with bias

Abstract

In the Halo Model, galaxies are hosted by dark matter haloes, while the haloes themselves are biased tracers of the underlying matter distribution. Measurements of galaxy correlation functions include contributions both from galaxies in different haloes, and from galaxies in the same halo (the so-called one-halo terms). We show that, for highly biased tracers, the one-halo term of the power spectrum obeys a steep scaling relation in terms of bias. We also show that the one-halo term of the trispectrum has a steep scaling with bias. The steepness of these scaling relations is such that the one-halo terms can become key contributions to the n-point correlation functions, even at large scales.We interpret these results through analytical arguments and semi-analytical calculations in terms of the statistical properties of haloes.