ALICE ITS3: a bent stitched MAPS-based vertex detector

Abstract: The ALICE ITS3 is a novel vertex detector replacing the innermost layers of ITS2 during LS3. Composed of three truly cylindrical layers of wafer-sized 65 nm stitched Monolithic Active Pixel Sensors, ITS3 provides high-resolution tracking of charged particles generated in heavy-ion collisions. This contribution presents an overview of the ITS3 detector, highlighting its design features, integration and cooling, and the ongoing development towards the final sensor. Furthermore, the paper introduces the off-detector service electronics, which play an essential role in the readout, control, and power supply of the detector.