This question is in reference to the paper here. In Equation (86) on page 28, the authors have given the two point correlation function
ξ(x−x′)=ξ1h(x−x′)+ξ2h(x−x′)
where the first term comes when we compute the density correlation using the same halo. The superscript
1h stands for "1 halo term" which is given by
ξ1h(x−x′)=∫dmm2n(m)ˉρ2∫d3y u(y|m)u(y+x−x′|m)
This term is easy to derive once we use formula (83). However, the issue is with the 2halo term which is:
ξ2h(x−x′)=∫dm1m1n(m1)ˉρ∫dm2m2n(m2)ˉρ∫d3x1u(x−x1|m1)∫d3x2u(x′−x2|m2)ξhh(x1−x2|m1,m2)
where
u is the normalized density profile i.e
∫d2x u(x−x′)=1. I have two questions regarding this:
- How do I exactly derive the 2halo term (I tried using Equation for ρ(x) as given in Equation (83) but, it does not give much).
- Also, what does the term ξhh physically imply?
This post imported from StackExchange Physics at 2014-07-28 11:15 (UCT), posted by SE-user Debangshu