Topological charge-sharing background reduction for the Silicon Drift Detectors used by the VIP experiment at LNGS

Large area Silicon Drift Detectors are employed in high sensitivity tests of the Pauli Exclusion Principle by the VIP-2 Collaboration. The experiment is operated in the extremely low cosmic background environment of the Gran Sasso underground National Laboratory of INFN. In this work an off-line analysis method is proposed which provides an additional background reduction, as well as a better calibration procedure. The study concerns in particular the charge sharing between nearby cells, and is applied to the data set collected during the 2018 VIP-2 campaign. The cross-talk effect inside the detectors array is described and an effective topological method to reject the background induced by charge sharing is outlined.