ATLAS ITk Layout Design and Optimisation

Detector design studies are a very crucial activity for the ATLAS Collaboration, in preparation for the future High Luminosity LHC (HL-LHC) planned to start in 2026. One of the key activities is the design and prototyping of a new Inner Tracker (ITk), fully made of silicon, able to meet the requirements HL-LHC environment assuring at the same time very high tracking performance. A dedicated design process started from Letter of Intent (LoI) layouts is still ongoing to establish the design ATLAS ITk tracker.