Speaker
Description
The $D^0 \to K_S^0 \pi^+ \pi^-$ decay channel plays a central role in precision studies of charm mixing and indirect CP violation.
In this talk, we present the status of the time-dependent binned analysis of this decay using data collected by the LHCb experiment during Run 3 in 2024.
This dataset benefits from the fully software-based trigger system introduced in Run 3, which significantly enhances the efficiency for reconstructing hadronic charm decays.
In particular, the new GPU-accelerated HLT1 trigger selects tracks based on displacement and kinematics using a refined approach compared to the Run 2 hardware-based system, which relied heavily on calorimetry.
This leads to a nearly threefold increase in signal yield per unit luminosity and a substantial reduction in trigger-induced correlations between decay time and Dalitz plot position, previously a dominant source of systematic uncertainty.
We present the analysis strategy and demonstrate the improved sensitivity to the mixing and CP-violating parameters x, y.
The results highlight the impact of the upgraded \lhcb trigger system in enabling more precise and robust charm physics measurements.