15
Large-scale
Distribution of Galaxies
•This function w(θ) describes apparent
clustering on
the sky down to some magnitude limit.
•More physically meaningful is the spatial two-point correlation function ξ(r) which describes clustering in 3-D about a
galaxy:
•Now N(r) dV describes the
number of galaxies in the volume element dV at a distance r from any galaxy. No is another normalization factorv
(ave.).