Does Antimatter Fall Like Matter?: Simulation of the GBAR Experiment

One of the main questions of fundamental physics is the action of gravity on antimatter. We present here the simulation of the last part of the experiment GBAR at CERN, i.e. the measurement of the free fall acceleration $\bar{g}$ of antihydrogen atoms in the gravitational field of the Earth. It includes the Monte-Carlo generation of trajectories and the analysis leading to the estimation of $\bar{g}$. A precision of the measurement beyond the % level is confirmed when taking into account the experimental design.