Mandate of Parameter and Lay out Committee (PLC) of the HL-LHC project

L. RossiHL-LHC PC

The PLC will establish and maintain a coherent and dynamic list of parameters and associated hardware lay-out for the HL-LHC. The list will include beam parameters, the new accelerator components including the ones interfacing with the experimental detectors, with their main characteristics and nominal performance. The PLC will maintain also a list of processes or operation cycles for the HL-LHC run. The PLC will monitor and recommend changes in parameters or machine layout based on interim reports from the workpackage (WP) leaders or any other relevant bodies. When applicable, it will also request dedicated studies to solve or mitigate any possible kind of inconsistencies and prepare the decision making process at the Steering Committee (SC).

The parameter list will be public, should be easily accessible and will be approved by the SC upon proposal by the PLC. It will then constitute the official reference for the project.The list will be part of the HL-LHC database and as such, the PLC chair will work closely with the Project Coordinator and with the Technical Coordinator.

Composition:

All main hardware groups of the CERN accelerator sector will be represented as well as the main WPs in which the project is subdivided. The PLC Chairperson proposes the membership for approval to the Steering Committee (SC) of the HL-LHC. The PLC will meet as many times as needed at discretion of the Chairperson, with a minimum of four times per year.

Chair (O. Bruning)The SC of HL-LHC appoints the chairperson for two years, and the mandate is renewable. The SC can dismiss the chairperson before the end of its mandate upon proposal by the Project Coordinator: in such a case a written motivation shall be duly notified to the PLC chair, eventually submitted to the SC for a formal vote, should the PLC chair contest the decision.The PLC chair is full member of the SC, with the same rights and obligations, in particular with voting right, except for non-technical matters related to EC-FP7 Design Study.The Chairperson will have the responsibility of collecting information across all WPs, of making a consistent list of parameters important for the upgrade and of maintaining sets of parameter values that may be employed for the HL-LHC. He/she will propose criteria for assessing the merit of different parameter sets with respect to the HL-LHC goals. The criteria will be discussed and endorsed by the SC, as well as the baseline parameter sets (and approved variants).In case of technical disagreement between PLC chair and one (or more) WP leader, the Project Coordinator will propose to solve it in the SC, eventually with a vote to which the PLC himself will participate.