Simulating optical galaxy clusters with realistic projection effects

The abundance of galaxy clusters is a sensitive probe for the growth of structure and cosmic acceleration. However, current optical cluster cosmology studies are limited by projection effects; that is, physically unassociated galaxies along a cluster's line of sight can be mistaken as cluster members. I will present an efficient and flexible approach for simulating the observed optical clusters incorporating projection effects. In particular, we use N-body simulations and a halo occupation distribution (HOD) model to simulate the population of red galaxies contributing to cluster members. We then use counts-in-cylinders to model the impact of projection on cluster richness. Our simulation framework paves the way for simulation-based cluster cosmology analyses.