Physics performance studies for the ALICE inner tracker upgrade

Abstract

During the second long shutdown of the LHC in 2018, the ALICE Collaboration plans to install an upgrade of the ALICE Inner Tracking System (ITS) in the central barrel with seven layers of silicon detectors starting at 2.2 cm radial distance from the interaction region and a material budget as low as 0.3% radiation length per layer. A single-hit resolution of $\mathrm{4 \mu m}$ and a readout rate capability of up to 50 kHz in Pb--Pb collisions will allow new and unique measurements in the heavy-quark sector, i.e. charm and beauty. Using detailed Monte Carlo simulations of pp and Pb--Pb collisions we study the performance for heavy-flavor detection with an upgraded ITS in the following benchmark analyses: Charm meson and baryon production, i.e. $\mathrm{D^{0} \rightarrow K^{-}\pi^{+}}$ and $\mathrm{\Lambda_{c}^{+} \rightarrow pK^{-}\pi^{+}}$, and beauty meson and baryon production, i.e. displaced vertices of $\mathrm{B^{+} \rightarrow \bar{D}^{0}\pi^{+}}$ and $\mathrm{\Lambda_{b} \rightarrow \Lambda_{c}^{+}\pi^{-}}$.