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Can $Z_{cs}(3985)$ be a molecular state of $bar{D}_s^*D$ and $bar{D}_sD^*$ ?

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 نشر من قبل Ming-Zhu Liu
 تاريخ النشر 2020
  مجال البحث
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We study the $Z_{cs}(3985)$ state recently observed by the BESIII Collaboration in the one-boson-exchange model, assuming that it is a $bar{D}_s^{(*)}D^{(*)}$ molecule, which has the quark content $cbar{c}sbar{q}$ with $q = u$, $d$. It is shown that the one-boson-exchange potential is too weak to generate dynamcally $bar{D}_s D$, $bar{D}^*_s D$, and $bar{D}_sD^*$ states, while for the case of $bar{D}^*_s D^*$, very loosely bound states are likely, with binding energies of the order of several MeV. We conclude that, the observed $Z_{cs}(3985)$ state, if confirmed by further experiments, cannot be a pure hadronic molecular state of $bar{D}_s D^*$ and $bar{D}_s^*D$ and could consist of large components of compact nature.

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