Velocity correlations in simulations and observations

We present an analysis of the two-point cosmic velocity correlation function. We calculate the correlations of the Cosmicflows catalogues and estimate the errors using the Millennium N-body simulations. We estimate the correlation coherence length, and combine the velocity correlation function expectations from linear theory to constrain the cosmological parameters $\Gamma$ and $\beta$. Using the maximum likelihood method, we find a value of $\Gamma=0.195^{+0.08}_{-0.045}$ (95\% CL) that is consistent with the Planck results.