论文标题
复杂缩放法下的双链四夸克
Double-charm tetraquark under the complex scaling method
论文作者
论文摘要
LHCB合作发现了一个双链Tetraquark $ t_ {cc}^{+} $，宽度很小。我们将$ t_ {cc}^{+} $作为$ dd^{*} $分子在单验交换潜在模型的框架中，带有$ j^{p} = 1^{+} $。同源破裂效果和$ S-D $ WAVE耦合被仔细考虑。我们采用复杂的缩放方法（CSM）来研究$ dd^{*} $系统，并获得与$ t_ {cc}^{+} $相对应的准状态。它相对于$ d^{0} d^{*+} $和宽度的绑定能量分别为$ -354 $ kev和$ 61 $ kev。发现Isospin破裂效果是巨大的，并且$ s $ wave $ d^{0} d^{*+} $和$ d^{+} d^{*0} $组件分别具有$ 72.1 \％$ $ $ 27.1 $和$ 27.1 \％$ $ $ $ $ $ $ $的概率。此外，我们在$ dd^{*} $系统中找不到任何共鸣。作为副产品，我们将$ x（3872）$研究为$（d \ bar {d}^* - d^*\ bar {d}）/\ sqrt {2} $分子，带有$ j^{pc} = 1^{++} $。我们还找到了与$ x（3872）$相对应的quasibound状态。它相对于$ d^{0} \ bar {d}^{*0} $阈值和宽度分别为$ -111 $ kev和$ 26 $ kev。 $ s $ wave $（d^{0} \ bar {d}^{*0} -d^{*0} \ bar {d}^{0}^{0}）/\ sqrt {2} $ component以$ 92.7 \％$ $ $ $ $ $ $ 92.7 \％$。
The LHCb Collaboration discovered a double-charm tetraquark $T_{cc}^{+}$ with a very small width. We investigate the $T_{cc}^{+}$ as a $DD^{*}$ molecule with $J^{P}=1^{+}$ in the framework of the one-boson-exchange potential model. The isospin breaking effect and $S-D$ wave coupling are taken into account carefully. We adopt the complex scaling method (CSM) to study the $DD^{*}$ system and obtain a quasibound state corresponding to the $T_{cc}^{+}$. Its binding energy relative to the $D^{0}D^{*+}$ and width are $-354$ keV and $61$ keV respectively. The isospin breaking effect is found to be enormous, and the $S-$wave $D^{0}D^{*+}$ and $D^{+}D^{*0}$ components give dominant contributions with the probabilities of $72.1\%$ and $27.1\%$ respectively. In addition, we do not find any resonances in the $DD^{*}$ system. As a by-product, we study the $X(3872)$ as a $(D\bar{D}^*-D^*\bar{D})/\sqrt{2}$ molecule with $J^{PC}=1^{++}$. We also find a quasibound state corresponding to the $X(3872)$. Its binding energy relative to the $D^{0}\bar{D}^{*0}$ threshold and width are $-111$ keV and $26$ keV respectively. The $S-$wave $(D^{0}\bar{D}^{*0}-D^{*0}\bar{D}^{0})/\sqrt{2}$ component dominates this state with the probability of $92.7\%$.
