Belle II: Evaluation of the neural network z-vertex trigger

The track trigger of the Belle II experiment will include a z-vertex trigger based on neural networks, whose purpose is to determine the origin of tracks and to suppress background coming from outside the interaction point of the colliding beams. The commissioning phase of the experiment, which has started in February 2018, will provide first real data to evaluate the z-vertex trigger, which has so far only been tested on simulated tracks. The task is to compare the results of the trigger to the full offline reconstruction and to measure the resolution of the z-vertex trigger. In addition, the background distribution has to be analyzed in order to determine a suitable cut for an efficient background suppression.

Prof. Dr. Christian Kiesling
Dr. Hans-Günther Moser