Rare charm decays D0 → hhee and long tracks reconstruction for the Run 3 trigger's HLT1 level

by Dr Alessandro Scarabotto (Sorbonne Université)

Wednesday 5 Apr 2023, 13:00 → 14:00 Europe/Berlin

CP-03-123 (TU Dortmund)

Rare charm decays are a unique up-type quark probe for Flavour Changing Neutral Current (FCNC) processes. The four-body D⁰ decays with electrons in the final state, D⁰ → ππee and D⁰ → KKee, are yet to observed and Beyond Standard Model (BSM) effects can enhance their rates and angular asymmetries. LHCb is performing the very first analysis on these decays using Run 2 data. The trigger efficiency on these decays can be improved during the Run 3 data taking by removing the L0 hardware trigger and selecting interesting events directly with a fully software trigger. Graphics Processing Units (GPUs) are used to perform the event reconstruction at the 30 MHz pp collision rate provided by the LHC. This quite demanding task requires optimized tracking algorithms with a good reconstruction efficiency meanwhile respecting tight throughput requirements. Long tracks, formed by particles traversing the full LHCb detector, are fundamental to select interesting events at LHCb and their reconstruction algorithm will be presented during the seminar.

slides.pdf