Mandate of the Phase II Upgrade Groups (P2UG), as reviewed in 2026

Preamble

The initial mandate of the P2UG was for two years, with the mention that they would remain in place until the installation of the upgrades during LS3. Following the delay in LS3, they stayed in place until end 2025.

Mandate of the P2UG

Following the end of the P2UG review process at the end of 2025, a new, more compact review mechanism for the Phase II upgrades of ATLAS and CMS that supports the regular review in the LHCC was put in place.

The review consists of two elements: Experiment-specific Expert Panels and a Joint Phase II Schedule Panel.

The Expert panels will be concentrating on the projects most critical for the LS3 schedule, currently expected to be ITk and Muon RPCs for ATLAS and Outer Tracker and HGCAL for CMS. The projects included in this review will be adjusted depending on progress and remaining challenges as the projects develop.

The Joint Phase II Schedule Panel will provide an assessment of the schedule situation of both upgrade projects and will produce a quarterly high-level overview, which will be reported to the LHCC, and may also be shared with the Scientific Policy Committee, Council and with the Resource Review Boards. The membership of the new review bodies will be established in discussions with the outgoing P2UG chairs.