PengCheng Hong | Searcharxiv

arXiv2025

Bell nonlocality and entanglement in $\chi_{cJ}$ decays into baryon pair

We present a systematic analysis of Bell nonlocality and entanglement in $\chi_{cJ}$($J=0,1,2$) decays into baryon pair($B\bar{B}$), with particular emphasis on their production via the process $e^+e^- \to \psi(2S) \to \gamma \chi_{cJ}$ at BESIII. From the baryon-antibaryon spin density matrix, we construct measurable Bell observables and concurrence, revealing a striking hierarchy of quantum correlations: $\chi_{c0}$ decays exhibit maximal violation and entanglement; $\chi_{c1}$ decays violate Bell inequalities for $\theta_1 \in (0, \pi)$ with angle-modulated strength; we find that the $B\bar{B}$ pair in $\chi_{c2}$ decays is in a separable state, and no indication of Bell inequality violation is observed. We provide complete analytical results for $J=0,1$ and quantitative, uncertainty-aware estimations for $J=2$ based on experimental inputs from BESIII. These results establish the $\chi_{cJ}$ system produced via this radiative transition as a novel and promising platform for testing quantum entanglement and Bell nonlocality in high-energy collisions.

hep-ph↗

arXiv2022

Study of parity violation in $\Lambda_c^+\to\phi p$ and $\Lambda_c^+ \to \omega p$ decays

Evidence for CP violation in baryonic decays has not been seen in experiments. With large data events accumulated at $e^+e^-$ collider or Large Hadron Collider, the charmed baryon decays would provide a promising laboratory to test the CP symmetry. In this work, we formulate the $\Lambda_c^+\to\phi p$ and $ \Lambda_c^+\to\omega p$ decays for the measurements of their asymmetry parameters in weak decays at the BESIII or the LHCb experiments. The polarization transfer is analyzed in the two processes of $e^+ e^- \to\Lambda_c^+\bar\Lambda_c^-$ and $\Lambda_b^0\to \Lambda^+_c\pi^-$, and the formulas of the joint angular distribution for these processes are provided. The sensitivity of the measurement of asymmetry parameters for the above two decay processes is estimated for the future experiments.

hep-ph↗