Comprehensive studies on calibration parameters of the LHCb Upstream Tracker

Abstract The Upstream Tracker is a novel silicon microstrip detector installed during LHCb Upgrade 1. To maintain the necessary efficiency, its performance requires constant monitoring and evaluation of the calibration parameters of over half a million sensors. Here, recent results regarding the stability and uniformity of those parameters are presented in order to establish whether the UT forms a stable detecting system supporting reliable physics results. The input data comprise calibration scans taken regularly in the second half of 2024. They contain information on the baseline offset and different noise components. We performed extensive studies regarding the time evolution of those parameters and their spatial distributions. Our results confirm that the Upstream Tracker demonstrates stable overall performance in all analysed calibration parameters. However, several local deviations have been identified, and an ongoing effort is being made to minimise their influence on the detector's performance.