CMS pixel detector extracted after 10 years of successful operations

The core of the CMS experiment, the pixel detector, has now been removed after 10 years of successful operations. The extraction took place over the course of one week. 

Originally proposed in 2010, the first upgrade of the pixel detector (Phase-1) was installed in early 2017 during the year-end technical stop. The detector was equipped with about 1800 modules, which each had 66’000 rectangular pixels. By recording signals left by charged particles, the detector enabled the reconstruction of tracks and collision vertices.

The Pixel detector took data throughout LHC Run 2 (2017-18) and Run 3 (2022-26), reaching the end of operations with about 95% of active channels, despite being exposed to more radiation than originally planned.

The team who built and operated the detector is now passing the baton to the new collaborators preparing the next pixel detector, called the Inner Tracker, with 4000 modules being assembled all around the world.