论文标题
$ z_c（3900）$和$ z_c（4020）$的奇怪分子合作伙伴
Strange molecular partners of the $Z_c(3900)$ and $Z_c(4020)$
论文作者
论文摘要
量子染色体动力学提出了一系列精确和近似的对称性，可以利用这些对称性来预测先前已知的黑核。 $ z_c（3900）$和$ z_c（4020）$共振，理论化为等级$ d^* \ bar {d} $和$ d^* \ bar {d}^* $ molecules [$ i^g（j^{pc}）在这里，我们认为，从su（3） - 味对称性中，我们应该期望$ z_c $的奇怪合作伙伴具有hadronic分子配置$ d^* \ bar {d} _s $ - $ d \ $ d \ bar {d} d} _s^* _s^* $ d $ d^* $ d^* $ d^* \ bar {d} d} $ c \ bar {c} s \ bar {q} $，带有$ q = u，d $）。这些$ z_ {cs} $和$ z_ {cs}^*$共振的量子号为$ i（j^p）$ = $ \ frac {1} {2} {2}（1^+）$。这些合作伙伴的预测群众取决于所使用的理论方案的细节，但它们应该围绕$ d^* \ bar {d} _s $ - $ d \ bar {d} _s _s^* $和$ d^* \ bar {d}^* \ bar {d}^*}^*} {*} _ s $ Thresholds。此外，这些状态中的任何一个都可以是虚拟极或共鸣。我们表明，加上可能的三角奇异性贡献，这样的图片与$ e^+e^ - \ to k^+的最新besiii数据非常吻合（d_s^-d^-d^{*0}+d_s+d_s^{* - * - } d^0）$。
Quantum Chromodynamics presents a series of exact and approximate symmetries which can be exploited to predict new hadrons from previously known ones. The $Z_c(3900)$ and $Z_c(4020)$ resonances, which have been theorized to be isovector $D^* \bar{D}$ and $D^* \bar{D}^*$ molecules [$I^G(J^{PC}) = 1^-(1^{+-})$], are no exception. Here we argue that from SU(3)-flavor symmetry, we should expect the existence of strange partners of the $Z_c$'s with hadronic molecular configurations $D^* \bar{D}_s$-$D \bar{D}_s^*$ and $D^* \bar{D}^{*}_s$ (or, equivalently, quark content $c\bar{c} s \bar{q}$, with $q = u, d$). The quantum numbers of these $Z_{cs}$ and $Z_{cs}^*$ resonances would be $I(J^P)$ = $\frac{1}{2}(1^+)$. The predicted masses of these partners depend on the details of the theoretical scheme used, but they should be around the $D^* \bar{D}_s$-$D \bar{D}_s^*$ and $D^* \bar{D}^{*}_s$ thresholds, respectively. Moreover, any of these states could be either a virtual pole or a resonance. We show that, together with a possible triangle singularity contribution, such a picture nicely agrees with the very recent BESIII data of the $e^+e^-\to K^+(D_s^-D^{*0}+D_s^{*-}D^0)$.
