Tracking and Flavour Tagging at FCC-hh

Tagging heavy flavour jets is crucial for many aspects of the FCC-hh physics programme, such as Higgs and top measurements, as well as searches for physics Beyond the Standard Model. The wide physics programme at FCC-hh requires excellent b-tagging and c-tagging capabilities for jets over a large energy range. The flavour tagging performance depends strongly on the track reconstruction capabilities. Therefore, the flavour tagging performance should be taken into consideration in the FCC-hh tracker design and optimisation. This note evaluates the tracking and flavour tagging performance expected at FCC-hh by using central di-jet events of various momenta in $\sqrt{s}$=100 TeV proton-proton collisions. The simulation and reconstruction is carried out using linear collider software tools. A CLIC_SiD-like detector where the tracker is replaced by the FCC-hh tracker is used in this study. The innermost tracker layers have typically the largest impact on the impact parameter resolution and thus on the flavour tagging performance. Therefore the performance is evaluated for variations of the innermost tracker layers in terms of granularity and material budget.