论文标题
揭示新观察到的$η_1（1855）$的内部结构
Revealing the inner structure of the newly observed $η_1(1855)$ via photoproduction
论文作者
论文摘要
最近，Besiii合作观察到了$ηη^{'} $不变的质谱的一种新的HADRONE奇异状态$η_1（1855）$。根据其特性，例如光谱和衰减宽度，$η_1（1855）$被认为是紧凑的多夸克状态，一个强子分子或混合膜。为了区分$η_1（1855）$的各种解释，提出了$η_1（1855）$ photoproduction the Proton靶标的零用模型。如果$η_1（1855）$是$ s \ bar {s} g $ hybrid meson，则可以通过primakoff效果产生$η_1（1855）$。但是，$η_1（1855）$ Photoproduction由$ t $ - channel vector Mesons $ρ$，$ω$和$ ϕ $ Exchange主导，假设$η_1（1855）$作为$ s $ s $ s $ s-Wave $ k \ bar bar \ bar {k} _1（1400）$ MECARELAL $ MEATERALEN。我们的计算表明，通过$γp$反应的$η_1（1855）$生产的总横截面可以达到0.115 pb，约为0.0124 $ \％$ \％$ \％$ \％$ \％$ $ \％$，通过考虑$η_1（1855）$作为$ s $ s $ s $ k $ k \ bar \ bar \ bar \ bar {k} {k} _1（1400）$ MOREC $ MOREC $ MOREC。我们还发现它们的线形状大不相同。如果$η_1（1855）$是一个分子状态，则阈值附近的$η_1（1855）$的光生效提供了测试其分子性质的好地方。但是，如果$η_1（1855）$是$ s \ bar {s} g $混合中介，则选择高能量，至少超过$e_γ= 16.97 $ GEV，观察$η_1（1855）$的产生。可以在中国的Gluex实验或电子离子对撞机中测量这些结果，以测试$η_1（1855）$的性质。
Very recently, a new hadronic exotic state $η_1(1855)$ at the invariant mass spectrum of $ηη^{'}$ was observed by the BESIII Collaboration. According to its properties, such as the spectroscopy and decay width, the $η_1(1855)$ have been suggested to be a compact multi-quark state, a hadron molecule, or a hybrid meson. In order to distinguish the various interpretations of the $η_1(1855)$, a Reggeized model combined with the vector dominance model for $η_1(1855)$ photoproduction on the proton target is presented. If the $η_1(1855)$ is a $s\bar{s}g$ hybrid meson, the $η_1(1855)$ can be produced though the Primakoff effect. However, the $η_1(1855)$ photoproduction is dominated by the $t$-channel vector mesons $ρ$, $ω$, and $ϕ$ exchange by assuming $η_1(1855)$ as an $S$-wave $K\bar{K}_1(1400)$ molecular state. Our calculations show that the total cross section of the $η_1(1855)$ production via $γp$ reaction can reach up to 0.115 pb, about 0.0124$\%$ of the total cross section obtained by considering the $η_1(1855)$ as an $S$-wave $K\bar{K}_1(1400)$ molecule. We also find their line shapes are sizably different. If the $η_1(1855)$ is a molecular state, the photoproduction of $η_1(1855)$ near the threshold offers a nice place to test its molecular nature. However, it should be better to take high energy, at least above $E_γ=16.97$ GeV, to observe the production of $η_1(1855)$ if $η_1(1855)$ is a $s\bar{s}g$ hybrid meson. These results can be measured in the GlueX experiment or Electron-Ion Collider in China to test the nature of the $η_1(1855)$.
