Track and Vertex Reconstruction on GPUs for the Mu3e Experiment

The Mu3e experiment searches for the lepton flavour violating decay μ → eee , aiming at a branching ratio sensitivity of 10 − 16 . A high precision tracking detector combined with timing detectors will measure the momenta, vertices and timing of the decay products of more than 10 9 muons/s stopped in the target. The trigger-less readout system will deliver about 100 GB/s of data. The implementation of a 3D tracking algorithm on a GPU is presented for usage in the online event selection. Together with a vertex fit this will allow for a reduction of the output data rate to below 100 M