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$bar{K}Lambda$ molecular explanation to the newly observed $Xi(1620)^0$

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 نشر من قبل Kan Chen
 تاريخ النشر 2019
  مجال البحث
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The newly observed $Xi(1620)^0$ by the Belle Collaboration inspires our interest in performing a systematic study on the interaction of an anti-strange meson $(bar{K}^{(*)})$ with a strange or doubly strange ground octet baryon $mathcal{B}$ ($Lambda$, $Sigma$, and $Xi$), where the spin-orbit force and the recoil correction are considered in the adopted one-boson-exchange model. Our results indicate that $Xi(1620)^0$ can be explained as a $bar{K}Lambda$ molecular state with $I(J^P)=1/2(1/2^-)$ and the intermediate force from $sigma$ exchange plays an important role. Additionally, we also predict several other possible molecular candidates, i.e., the $bar{K}Sigma$ molecular state with $I(J^P)=1/2(1/2^-)$ and the triply strange $bar{K}Xi$ molecular state with $I(J^P)=0(1/2^-)$.

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