April 29, 2019

Peak Patch Halo Selection

These are the steps that I use to select halos from the full-sky high-redshift Peak Patch lightcone run.

1) Project all the halos onto a Healpix map. Keep only the ones that fall in the same sky regions I defined for the DES clusters and CMASS galaxies. I keep a larger rectangle of galaxies than of clusters because I don't want clusters on the edge to have strange orientation effects.

2) From this reduced catalog take an approximately Gaussian distribution of masses centered on logM = 12.87 (where M is in M_sun) with a standard deviation of 0.37, which should match the CMASS sample. See Figure 1.

3) Divide these halos into bins of 100 Mpc. For each bin, take a random sample of n halos, where n is the number of CMASS galaxies in that region of redshift space.

4) For the clusters, take the sample left after step 1 and for every 100 Mpc bin, keep the top x halos. Here x is the number of DES Redmapper clusters in that region of redshift space.