论文标题
$ b^0 \toπ^ - k^+ x（3872）$ in $ d_ {s1} \ bar {d} d^*$ loop和$ x（3872）$质量的可能的精确度量
Triangle singularity in $B^0\to π^- K^+ X(3872)$ via the $D_{s1}\bar{D} D^*$ loop and possible precise measurement of the $X(3872)$ mass
论文作者
论文摘要
我们通过$ d_ {s1}（2536）（2536）\ bar {d} d^*$ rectatering图调查了$ b^0 \ toπ^-k^+ x（3872）$衰减。 $ k^+x（3872）$分布曲线的线形在$ d_ {s1}（2536）（2536）\ bar {d} $阈值对$ x（3872）$质量非常敏感，因为三角形奇异性（TS）可以从循环中产生。通过这种特征，我们可以确定$ x（3872）$质量是低于还是高于$ d^{\ ast 0} \ bar {d}^0 $ threshold，均高精度。循环中$ d_ {s1}（2536）$的狭窄是TS测量$ x（3872）$质量可以起作用的TS机制的关键原因之一。 $ x（3872）$宽度对$ k^+x（3872）$线形状的影响在TS机构中也至关重要。如果宽度与1 MeV一样大，则建议测量$ x（3872）$质量的拟议方法会被破坏。
We investigate the $B^0\to π^- K^+ X(3872)$ decay via the $D_{s1}(2536)\bar{D} D^*$ rescattering diagram. The line shape of the $K^+X(3872)$ distribution curve around $D_{s1}(2536)\bar{D}$ threshold is very sensitive to the $X(3872)$ mass because the triangle singularity (TS) can be generated from the loop. By means of this characteristic, we can determine whether the $X(3872)$ mass is below or above the $D^{\ast 0}\bar{D}^0$ threshold with high precision. The narrowness of $D_{s1}(2536)$ in the loop is one of the key reasons why the TS mechanism of measuring the $X(3872)$ mass may work. The $X(3872)$ width impact on the $K^+X(3872)$ line shape is also crucial in the TS mechanism. If the width is as large as 1 MeV, the proposed method of measuring the $X(3872)$ mass would be ruined.
