论文标题
探索$ e^+e^ - \toλ_c^+λ_c^ - $交叉部分
Exploring the $e^+e^-\to Λ_c^+Λ_c^-$ cross sections
论文作者
论文摘要
同时对$ e^+e^ - \至λ_c^+λ_c^ - $ cross截面数据由belle和besiii从阈值开始为5.4 GEV。为了适应阈值接近的BESIII测量和对共振$ y（4630）$的Belle观察，我们构建了一个具有Breit-wigner共振的复合PDF，并为建模$ E^+E^+E^+e^toλ_c^+λ_c^+λ_c^ - $ $ e^+e^+e^+e^+e^+e^+e^+e^+e^+E^+E^+evigner的贡献做出了贡献。拟合的质量为$ m = [4636.1 _ { - 7.2}^{+9.8}（$ stat $）\ pm 8.0（$ syst $）] $ 〜Mev/$ c^2 $，宽度为$γ_{\ rm tod} 5.6（$ syst $）] $ 〜MeV，和$γ_{e^+e^ - } \ Mathcal {b} [y（4630）\toλ_c^+λ_c^ - ] = [18.3 _ { - 6.1}我们研究中$ Y（4630）$的宽度比以前的Belle贴合窄。 $ Y（4630）$的质量和宽度也与矢量共振$ y（4626）$最近在$ d_s^+d_ {s1}（2536）^ - $ by Belle中显示出良好的协议。
A simultaneous fit is performed to the $e^+e^-\to Λ_c^+Λ_c^-$ cross section data measured by Belle and BESIII from threshold up to 5.4 GeV. In order to accommodate both the BESIII measurement near threshold and the Belle observation of a resonance $Y(4630)$, we build a composite PDF with a Breit-Wigner resonance and a continuum contribution to model the full cross section line shape of $e^+e^-\to Λ_c^+Λ_c^-$. The fit gives a mass of $M=[4636.1_{-7.2}^{+9.8} ($stat$)\pm 8.0($syst$)]$~MeV/$c^2$, a width of $Γ_{\rm tot}=[34.5_{-16.2}^{+21.0} ($stat$)\pm 5.6($syst$)]$~MeV, and $Γ_{e^+ e^-}\mathcal{B}[Y(4630)\toΛ_c^+Λ_c^-]=[18.3_{-6.1}^{+8.8} ($stat$)\pm 1.1($syst$)]$~eV/$c^2$ for the resonance. The width of $Y(4630)$ from our study is narrower than the previous Belle fit. The mass and width of $Y(4630)$ also show good agreement with a vector resonance $Y(4626)$ recently observed in $D_s^+D_{s1}(2536)^-$ by Belle.
