Performance of the Gas Gain Monitoring system of the CMS RPC muon detector and effective working point fine tuning

TL;DR

This paper evaluates the Gas Gain Monitoring system of the CMS RPC muon detector, focusing on its stability, feedback control algorithms, and methods for fine-tuning the detector's effective working point.

Contribution

It introduces and assesses a feedback algorithm for maintaining stable detector response despite environmental variations, enhancing the GGM system’s performance.

Findings

Feedback algorithm effectively stabilizes detector response

Alternative algorithms show comparable or improved performance

System maintains stability despite temperature and pressure changes

Abstract

The Gas Gain Monitoring (GGM) system of the Resistive Plate Chamber (RPC) muon detector in the Compact Muon Solenoid (CMS) experiment provides fast and accurate determination of the stability in the working point conditions due to gas mixture changes in the closed loop recirculation system. In 2011 the GGM began to operate using a feedback algorithm to control the applied voltage, in order to keep the GGM response insensitive to environmental temperature and atmospheric pressure variations. Recent results are presented on the feedback method used and on alternative algorithms.