RPC upgrade project for CMS Phase II

TL;DR

The CMS Phase II Muon Upgrade enhances detector coverage and performance for HL-LHC by developing and testing improved RPCs with high-pressure laminate technology suitable for high-background environments.

Contribution

This paper presents the R&D and testing of new RPC prototypes using HPL technology for the CMS Phase II upgrade, a novel approach for high-background conditions.

Findings

HPL double-gap RPCs are suitable for high background environments.

Prototypes tested successfully at CERN's GIF++ facility.

Upgrade plans are aligned with the Long Shutdown 3.

Abstract

The Muon Upgrade Phase II of the Compact Muon Solenoid (CMS) aims to guarantee the optimal conditions of the present system and extend the $\eta$ coverage to ensure a reliable system for the High Luminosity Large Hadron Collider (HL-LHC) period. The Resistive Plate Chambers (RPCs) system will upgrade the off-detector electronics (called link system) of the chambers currently installed chambers and place improved RPCs (iRPCs) to cover the high pseudo$-$rapidity region, a challenging region for muon reconstruction in terms of background and momentum resolution. In order to find the best option for the iRPCs, an R\&D program for new detectors was performed and real size prototypes have been tested in the Gamma Irradiation Facility (GIF++) at CERN. The results indicated that the technology suitable for the high background conditions is based on High Pressure Laminate (HPL) double-gap RPC. The RPC Upgrade Phase II program is planned to be ready after the Long Shutdown 3 (LS3).