$e^+e^-\to η_cJ/ψ$ 产生及全粲四夸克态搜寻在STCF上的可行性研究

中文摘要 AI 辅助

拟议的高亮度超级τ-粲工厂（STCF）为奇特强子的阈值研究提供了清洁的实验环境。在本信中，我们评估了在STCF上通过$e^+e^- \to \eta_c J/\psi$ 道搜寻全粲矢量四夸克候选态$T_{4c}$的预期显著性。利用从$\sqrt{s}=6.71$到$6.79~\mathrm{GeV}$、每点$100~\mathrm{fb}^{-1}$的能量扫描的蒙特卡罗模拟，我们采用高效率的单标记（ST）重建$J/\psi$轻子衰变作为主要策略，并保留双标记（DT）重建$\eta_c \to K^+K^-\pi^0$作为独立的交叉检验。由于信号截面受仍不确定的双电子宽度$\Gamma_{ee}$支配，我们考虑了三个基准假设：$\Gamma_{ee}=0.25, 0.5, 1~\mathrm{eV}$。对应的预期ST显著性分别为$5.1\\,\sigma$、$10.6\\,\sigma$和$20.5\\,\sigma$。这些结果表明，STCF可以对阈值附近的全粲四夸克态提供有意义的灵敏度。

英文摘要

The proposed high-luminosity Super Tau-Charm Facility (STCF) offers a clean experimental environment for threshold studies of exotic hadrons. In this Letter, we evaluate the expected significance for the fully-charmed vector tetraquark candidate $T_{4c}$ in the $e^+e^- \to η_c J/ψ$ channel at the STCF. Using Monte Carlo simulations of an energy scan from $\sqrt{s}=6.71$ to $6.79~\mathrm{GeV}$ with $100~\mathrm{fb}^{-1}$ per point, we adopt a high-efficiency single-tag (ST) reconstruction of $J/ψ$ leptonic decays as the primary strategy, with a double-tag (DT) reconstruction of $η_c \to K^+K^-π^0$ retained as an independent cross-check. Because the signal cross section is governed by the still-uncertain dielectron width $Γ_{ee}$, we consider three benchmark hypotheses, $Γ_{ee}=0.25, 0.5, 1~\mathrm{eV}$. The corresponding expected ST significances are $5.1\,σ$, $10.6\,σ$, and $20.5\,σ$, respectively. These results indicate that the STCF can provide meaningful sensitivity to fully-charmed tetraquark states near threshold.

发表机构

• Sun Yat-Sen University（中山大学）
• University of Science and Technology of China（中国科学技术大学）
• University of Chinese Academy of Sciences（中国科学院大学）

机构由 AI 辅助整理，请以论文原文为准。