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arXiv · 2610.36529

Prospects for exploring quantum-correlated neutral $D\overline{D}$ decays at STCF

Ying-Hao Wang·Yi-Feng Wu·Pei-Rong Li·Yu Zhang·Xiao-Rui Lyu
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Abstract

We investigate the prospects for determining charm mixing, indirect $C\!P$ violation and hadronic parameters in charm decays with quantum-correlated neutral charm mesons at the proposed Super Tau-Charm Facility. The study is based on time-integrated double tag rates of coherent $D\overline{D}$ pairs produced at $\sqrt{s}=3.773$ and $4.030$ GeV, from $e^{+}e^{-}\to D^{(*)}\overline{D}^{(*)}$ processes. Here, one $D$ is tagged with the quasi flavour-specific decays $D\to K^-π^+π^+π^-$, $K^-π^+π^0$, and $K^-π^+$, while the other $\overline{D}$ is detected with the final states in flavour-specific mode, $C\!P$ eigenstate mode, or self-conjugate mode. The expected sensitivities are evaluated assuming an integrated luminosity of $1~{\rm ab}^{-1}$ at each energy point, demonstrating the capability on precise determination of the charm mixing parameters, the indirect $C\!P$ violation parameters, the strong-phase differences, and the coherence factors. The constraints of the hadronic-parameters provide unique inputs to the CKM angle $γ$ fit, while the measurements of charm mixing and indirect $C\!P$ violation parameters are complementary to the time-dependent measurements in the Belle II and LHCb experiments.

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Ying-Hao Wang, Yi-Feng Wu, Pei-Rong Li, Yu Zhang, Xiao-Rui Lyu. 2026-10-27. Prospects for exploring quantum-correlated neutral $D\overline{D}$ decays at STCF. https://arxiv.org/abs/2610.36529

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