Precision Validation of the Performance of the OTMB System for the CMS Muon Trigger

Abstract

Proton-proton collisions in the Large Hadron Collider (LHC) produce a number of particles and it takes a large detector to make precision measurements to identify all of them. The Compact Muon Solenoid (CMS) is one of the large general-purpose detectors at the LHC. The data collected is used to perform precision analyses to identify interesting physics events and compare them with theoretical predictions. It operates by measuring the particles produced through different layers of sub-detectors that measure different properties, such as the tracking detectors, calorimeters, and the muon detectors. The data coming from the sub-detectors are so large that it is impossible to save everything. Instead, only the most interesting events are identified for analyses. The trigger system in CMS is designed to make fast decisions for each collision event and identify them as interesting physics or as background with high efficiency. Within the CMS Muon system, it is important to ensure that the trigger decisions are made efficiently and reliably. The CMS muon trigger test stand at Texas A&M is used for validating the performance of the muon trigger algorithm. This is done by transmitting realistic collision data to the Optical Trigger Mother Board (OTMB) through a muon detector emulator board in a controlled way. The software that controls the test stand injects event data from full CMS detector simulations and verifies that the trigger OTMB decisions in the real hardware match with the trigger decisions predicted in simulation. Using this test stand, the research project will make precision measurements with the OTMB to verify the trigger algorithm and validate the performance of the CMS muon trigger system.