Search for $K^-pp$ bound state via $γd \rightarrow K^+ π^-X$ reaction at $E_γ=1.5-2.4$ GeV
A. O. Tokiyasu, M. Niiyama, J. D. Parker, D. S. Ahn, J. K. Ahn, S. Ajimura, H. Akimune, Y. Asano, W. C. Chang, J. Y. Chen, S. Daté, H. Ejiri, H. Fujimura, M. Fu… 展开作者
A. O. Tokiyasu, M. Niiyama, J. D. Parker, D. S. Ahn, J. K. Ahn, S. Ajimura, H. Akimune, Y. Asano, W. C. Chang, J. Y. Chen, S. Daté, H. Ejiri, H. Fujimura, M. Fujiwara, S. Fukui, S. Hasegawa, K. Hicks, K. Horie, T. Hotta, S. H. Hwang, K. Imai, T. Ishikawa, T. Iwata, Y. Kato, H. Kawai, K. Kino, H. Kohri, Y. Kon, N. Kumagai, D. L. Lin, Y. Maeda, S. Makino, T. Matsuda, T. Matsumura, N. Matsuoka, T. Mibe, M. Miyabe, M. Miyachi, N. Muramatsu, R. Murayama, T. Nakano, Y. Nakatsugawa, M. Nomachi, Y. Ohashi, H. Ohkuma, T. Ohta, T. Ooba, D. S. Oshuev, C. Rangacharyulu, S. Y. Ryu, A. Sakaguchi, T. Sawada, P. M. Shagin, Y. Shiino, H. Shimizu, E. A. Strokovsky, Y. Sugaya, M. Sumihama, J. L. Tang, Y. Toi, H. Toyokawa, T. Tsunemi, M. Uchida, M. Ungaro, A. Wakai, C. W. Wang, S. C. Wang, K. Yonehara, T. Yorita, M. Yoshimura, M. Yosoi, R. G. T. Zegers
A search for $K^-pp$ bound state (the lightest kaonic nucleus) has been performed using the $γd \rightarrow K^+ π^- \rm{X}$ reaction at E$_γ$=1.5-2.4 GeV at LEPS/SPring-8. The differential cross section of $K^+ π^-$ photo-production off deuterium has been measured for the first time in this energy region, and a bump structure was searched for in the inclusive missing mass spectrum. A statistically significant bump structure was not observed in the region from 2.22 to 2.36 GeV/$c^2$, and the upper limits of the differential cross section for the $K^-pp$ bound state production were determined to be 0.1$-$0.7 $μ$ b (95$%$ confidence level) for a set of assumed binding energy and width values.
Non-mesonic decay of the $η$-mesic $^{3}\hspace{-0.03cm}\mbox{He}$ via $pd\rightarrow(^{3}\hspace{-0.03cm}\mbox{He}$-$η)_{bound}\rightarrow$ $^{3}\hspace{-0.03cm}\mbox{He} 2γ(6γ$) reaction
First Model-Independent Measurement of the Spin Triplet $pΛ$ Scattering Length from Final State Interaction in the $\vec{p}p \rightarrow pK^{+}Λ$ Reaction
Measurements of the $γ_{v} p \rightarrow p' π^{+} π^{-}$ cross section with the CLAS detector for $0.4$ GeV$^{2}$ $< Q^{2} <$ $1.0$ GeV$^{2}$ and $1.3$ GeV $< W <$ $1.825$ GeV
新的结果上的单微分和全积分截面的过程$γ_{v} p \rightarrow p' π^{+} π^{-}$。实验数据是用杰斐逊实验室的CLAS探测器收集的。在运动学区域的反应不变质量$W$从1.3到1.825 GeV和光子虚$Q^2$从0.4到1.0 GeV $^2$进行测量。横截面中获得窄$Q^{2}$箱（0.05 GeV $^{2}$）与最小的统计不确定性达到双π介子电生产实验的日期。结果发现，在重叠的地方，与以前可用的数据一致。提取的截面，这是基于一个唯象的介子重子反应模型的初步解释，揭示了大量的相对贡献核子共振。这些数据提供了有前途的前景，以提高知识的$Q^{2}$ -进化的电耦合的大多数共振质量高达$\sim$ 1.8 GeV。
First exclusive measurements of the K^-pp state - populated in the pp to K^+ Lambda p reaction at 2.85 GeV
我们分析了在T_p = 2.85 $ GeV to search for a K^-pp (= X) nuclear bound state to be formed in the pp to K^+ + X reaction. The deviation spectra of the K^+ missing-mass MM (K^+) and Lambda p invariant-mass M(Lambda-p) with selection of large-angle proton emission revealed a structure with M_X = 2265 +- 2 MeV/c2 and Gamma_X = 118 +- 8$ MeV时，从pp到K^+ λ p的排它过程的DISTO实验数据。
Partial-wave analysis of $\bar K N$ scattering reactions
我们通过单能分波分析研究了两体反应$\bar K N\rightarrow \bar K N$、$\bar K N\rightarrow πΛ$和$\bar K N\rightarrow πΣ$。能量范围1480 - 2100 MeV。因此，提取的这些反应的分波振幅的多通道能量依赖模型满足的分波$S$矩阵的么正性的约束。我们得到了很好的预测微分截面，极化，极化截面，和截面这些反应从一个全球性的能量依赖的解决方案。
The $K^- p \rightarrow ηΛ$ reaction in an effective Lagrangian model
我们报告的理论研究的$K^- p \to ηΛ$反应阈值附近使用有效的拉格朗日方法。考虑了$s-$通道$Λ(1670)$、$t-$通道$K^*$和$u-$通道质子极图的作用。我们表明，总的截面数据是很好地再现。然而，仅考虑$s-$波$Λ(1670)$态以及$t-$和$u-$通道的背景贡献并不足以描述$K^- p \to ηΛ$反应角分布中的碗状结构，这表明在某些能量区域应该存在对该反应有贡献的较高分波.事实上，如果我们考虑来自$D_{03}$共振的贡献，我们可以描述碗结构，然而，需要相当小的宽度（$\sim 2$ MeV）的这种共振。
