Study of the efficiency of the first CMS High Level Trigger using tagged protons

The Precision Proton Spectrometer (PPS) is a subdetector of the CMS experiment and uses silicon pixel tracking detectors to measure protons scattered at very small angles. A High Level Trigger (HLT) consists of an array of processors that execute an accelerated version of the event reconstruction algorithm, and is responsible for reducing the event rate to around 1 kHz before data storage. This study focuses on the determination of the efficiency of the first CMS jet matching HLT using data from LHC run 3, before TS1, involving three eras. The efficiency of the HLT is determined by comparison with a looser HLT. Differences between the three eras are spotted in some properties of the jets. Some differences are also identified between events failing the HLT and events passing HLT.