A self-seeded track trigger for the FCC-hh

The feasibility of using a triplet of tracking layers in the barrel of the FCC-hh detector as a self-seeded track trigger is investigated. We find that a triplet of tracking layers is sufficient to reconstruct tracks with close to 100% efficiency, while giving a relatively low average fake rate of 0.5% for tracks with $p_{\mathrm{T}} > 2$ GeV, despite the intense pileup conditions expected at the FCC with an average of 1000 vertices per bunch crossing. Algorithms are explored to identify the primary vertex, and the region in which the primary vertex is can be found with an efficiency of 83%. Using tracks from this region, the triplet is capable of triggering on signal events of interest to the FCC-hh detector with an acceptance of 50% for 100 kHz rate.