ENVIRONMENT DEPENDENCE OF DARK MATTER HALOS IN SYMMETRON MODIFIED GRAVITY

We investigate the environment dependence of dark matter halos in the symmetron modified gravity scenario. The symmetron is one of three known mechanisms for screening a fifth force and thereby recovering general relativity in dense environments. The effectiveness of the screening depends on both the mass of the object and the environment it lies in. Using high-resolution N-body simulations we find a significant difference, which depends on the halo's mass and environment, between the lensing and dynamical masses of darkmatter halos similar to the f(R) modified gravity. The symmetron can however yield stronger signatures due to a freedom in the strength of coupling to matter.