Presentation #347.02 in the session Dark Matter & Dark Energy — iPoster Session.
N-body simulations are the main method used to model the cosmological dynamics of dark matter. A key prediction from such simulations is the amount of small-scale structure of the universe present in the form of dark matter halos. To quantify this, halo-finding algorithms are used to return a count of the halos and subhalos identified in the simulation data. If the halo-finder does not return an accurate count, this may lead to biased answers when these results are applied to observational data to constrain dark matter physics. In this project, we determine the detection efficiency of the Rockstar halo-finder. We perform numerical experiments in which we create N-body realizations of dark matter halos and subhalos with known properties. We find that the properties that are most influential on Rockstar’s detection efficiency for subhalos include the virial mass and radial distance from the host halo. This poster will describe the methods we used to determine the detection efficiency of Rockstar as a function of these properties. We present our analysis of the detection efficiency and the accuracy of the mass returned by Rockstar. This work may be used as a correction factor to the subhalo counts made by Rockstar, and thus has the potential to improve the accuracy of constraints derived on the particle properties of dark matter.