The Neuro-Z-Vertex Trigger of the Belle II Experiment

¹ Technische Universität München, Germany
² Max-Planck-Institut für Physik, München, Germany

^a e-mail: sebastian.skambraks@tum.de

Published online: 15 November 2016

Abstract

A neural network z vertex trigger is planned for the upcoming Belle II detector at the SuperKEKB collider. This neural algorithm is based on a single track 3D parameter estimation using only hit and drift time information from the central drift chamber. Due to the high luminosity (L = 8 × 10³⁵ cm⁻² s⁻¹) Belle II will have to face high levels of beam induced background, making a z vertex reconstruction at the first level trigger mandatory. Using the neural z vertex algorithm, the requirements of the standard track trigger can be strongly relaxed. By this, the trigger efficiencies, especially for low multiplicity events, e.g. τ pair production, can be significantly increased.

This contribution presents the foreseen neural network trigger setup and the preceding 2D track finder. Special focus is put on the proposal and evaluation of a possible 3D upgrade of the 2D track finder. Additionally, details are given on a dedicated setup for the upcoming cosmic ray test.