Scintillating Beauty
The Large Hadron Collider beauty (LHCb) experiment is designed to study the heavy flavour sector of the Standard Model (SM). Due to the excellent performance of the detector during LHC Run 1 and Run 2, the LHCb experiment has extended its physics program beyond the heavy flavour sector. To further exploit the experiment’s potential, the detector underwent a major upgrade between 2019-2022. In his thesis, Jan de Boer focuses in particular on the Scintillating Fibre (SciFi) tracker as part of the LHCb upgrade and on the analysis of Lepton Flavour Universality (LFU) in rare Λb → Λℓℓ decays using data from LHC Run 1 and Run 2.
The SciFi tracker is part of a new generation of detector that enable online readout at the bunch-crossing rate of 40 MHz and with an instantaneous luminosity five times higher than before. To ensure the expected performance of the SciFi tracker over its lifetime, the SiPM sensors need to be cooled down to -40 °C, which introduces supplementary services. De Boer presents a detailed analysis of the operational parameter space of the detector services. Additionally, he developed a detector control system (DCS) to continuously monitor and control these detector services.
The analysis of rare Λb → Λℓℓ decays aims to measure LFU through a double-ratio method, which helps to reduce systematic uncertainties on both the electron and muon decays. De Boer presents a study on the backgrounds present in the control and normalization channels used in the double-ratio measurement.
Read more: The long search for new physics