4-Dimensional Event Building in the First-Level Event Selection of the CBM Experiment

The future heavy-ion experiment CBM (FAIR/GSI, Darmstadt, Germany) will focus on the measurement of very rare probes at interaction rates up to 10 MHz with data flow of up to 1 TB/s. The beam will provide free stream of beam particles without bunch structure. That requires full online event reconstruction and selection not only in space, but also in time, so-called 4D event building and selection. This is a task of the First-Level Event Selection (FLES). (paper)