Magnus Mager - The ALICE Vertex Detector (ITS3) for LS3

ALICE is developing a novel vertex detector, "ITS3", to upgrade its experiential apparatus in LHC Long Shutdown 3 (LS3), in 2026-2028. It will be based on a newly developed detector concept that is based on ultra-thin (<50 μm), wafer-scale (up to ~10 ⨉ 26 cm² in size on 300 mm wafers) Monolithic Active Pixel Sensors (MAPS) that are fabricated in a 65 nm CMOS process. These sensors are then flexible enough to be bent to radii down to 18 mm, allowing to build truly cylindrical detector shells.

This development includes a number of cutting edge R&D efforts, including the qualification of MAPS in 65 nm, the development of wafer-scale stitched MAPS, the concept of bent MAPS, ultra-light mechanics based on carbon foam supports, and air-cooling -- many of which are firsts in HEP.

The seminar gives and overview of silicon sensors in ALICE, reviews shortly the motivations for the new vertex detector, and then dives into a number of selected recent R&D results. Finally an outlook towards the detector construction over the next years as well as future prospects of the technology will be given.