Prospects for P and C P violation in Λ c + decays with a polarized beam at the Super Tau-Charm Facility

Weak decays of the charmed baryons offer an ideal platform to study parity ( P ) and charge conjugation-parity ( C P ) violation in the quark sector, to stringently test the Standard Model and search for new physics. It is a key goal in the next-generation positron-electron collider, such as the Super Tau-Charm Facility (STCF). Thanks to the quantum-entangled pair production with superhigh luminosity and the possibility of beam polarization, STCF provides a unique environment to probe such symmetry violations with unprecedented sensitivity. In this paper, we evaluate the precisions of the P -violating parameters and subsequently obtain the expected sensitivity of the C P -violating parameters in charmed baryon decays of Λ c + → p π 0 , p η , Λ K + , Σ 0 K + , and Σ + K S 0 , regarding to different polarization setups in STCF. The study suggests that the implementation of longitudinal beam polarization in STCF would greatly enhance the experimental capability in studying P and C P violation.