$K^{+}\mathrm{\Lambda }(1405)$ photoproduction has been studied at the BGOOD experiment via the all neutral decay, $\mathrm{\Lambda }(1405)\to {\mathrm{\Sigma }}^0{\pi }^0$. The unique BGOOD experimental setup allows both the cross section and $\mathrm{\Lambda }(1405)$ invariant mass distribution (line shape) to be measured over a broad $K^{+}$ polar angle range, extending to extreme forward $K^{+}$ angles unattainable at previous experiments.

Evidence is provided for the role of a triangle singularity driven by the $N^{⁎}(2030)$ resonance, which appears to contribute significantly to $K^{+}\mathrm{\Lambda }(1405)$ photoproduction. This is observed in the integrated cross section which was determined with unprecedented energy resolution and supported by the angular distributions. The measured line shape is also in agreement with the previous results of CLAS and ANKE, and is consistent with two poles derived in χPT based models.

${ķ}^{+}\mathrm{\Lambda }(1405)$BGOOD 实验通过全中性衰变研究了光产生，$\mathrm{\Lambda }(1405)\to {\mathrm{\Sigma }}^0{\pi }^0$. 独特的 BGOOD 实验装置允许横截面和$\mathrm{\Lambda }(1405)$在宽范围内测量的不变质量分布（线形）${ķ}^{+}$极角范围，延伸至极前${ķ}^{+}$以前的实验中无法达到的角度。

为三角形奇点的作用提供了证据${ñ}^{⁎}(2030)$共振，这似乎对${ķ}^{+}\mathrm{\Lambda }(1405)$照片制作。这在以前所未有的能量分辨率确定并由角分布支持的综合横截面中观察到。测得的线形也与 CLAS 和 ANKE 先前的结果一致，并且与基于χ PT 的模型中得出的两个极点一致。