Track average cluster size for the ALICE ITS2

The Inner Tracking System (ITS) of the ALICE experiment at the Large Hadron Collider was upgraded during Long Shutdown 2. The upgraded ITS consists of seven layers of ALPIDE monolithic active pixel sensors. I will describe the average hit cluster size on pixel layers traversed by charged particles, along with simulations of the cluster sizes. This observable allows for isolating discrepancies between data and simulation without drawing on truth-level information, or responses from multiple systems. I will then demonstrate how track kinematics can overcome tracking detectors' limitations in particle identification to compare simulation and data, again with no additional truth-level information or inputs from other detectors. Finally, I will present current results for the newly-upgraded ITS2 during the most recent Run 3 at the Large Hadron Collider.