apply this transformation to the simulation particles as well as to the halo catalogue. We then select “edge-on” haloes from the simulation, by requiring that their angular momentum is at an angle less than $60^o$ from the sky, represented by the $x-y$ plane [^2]. We can then study two projected correlation functions centred in these objects using DM particles, (i) a correlation function calculated using pairs that subtend an angle with the projected angular momentum of less than $30^o$, which we call the parallel projected correlation function ($\omega_{||})$, and (ii) a perpendicular projected correlation function ($\omega_{\bot}$) obtained by counting pairs that subtend an angle greater than $60^o$ from the projected angular momentum.

Figure \[fig:projsim\] shows the results from this procedure. The left panels show the results for low mass haloes in the small simulation (projected correlation functions in the top-left, and ratios in the bottom-left), whereas the right panels show the results for high mass haloes in the large simulation. As can be seen, these results are qualitatively consistent with the alignment signal found in the previous subsection using the full three-dimensional correlation function, which indicates that projected correlation functions are a suitable tool to detect this effect. The overall 