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The $1D$, $2D$ $Xi_{b}$ and $Lambda_{b}$ baryons

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 نشر من قبل Guo-Liang Yu
 تاريخ النشر 2021
  مجال البحث
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Recently, scientists have made great progresses in experiments in searching for the excited states of $Xi_{b}$ and $Lambda_{b}$ baryons such as the $Lambda_{b}(6072)$, $Lambda_{b}(6146)$, $Lambda_{b}(6152)$, $Xi_{b}(6227)$, $Xi_{b}(6100)$, $Xi_{b}(6327)$ and $Xi_{b}(6333)$. Stimulated by these progresses, we give a systematical analysis about the $1D$ and $2D$ states of $Xi_{b}$ and $Lambda_{b}$ baryons with the method of QCD sum rules. By constructing three types of interpolating currents, we calculate the masses and pole residues of these heavy baryons with different excitation modes $(L_{rho},L_{lambda})=(0,2)$, $(2,0)$ and $(1,1)$. As a result, we decode the inner structures of $Lambda_{b}(6146)$, $Lambda_{b}(6152)$, $Xi_{b}(6327)$ and $Xi_{b}(6333)$, and favor assigning these states as the $1D$ baryons with the quantum numbers $(L_{rho},L_{lambda})=(0,2)$ and $frac{3}{2}^{+}$, $frac{5}{2}^{+}$, $frac{3}{2}^{+}$ and $frac{5}{2}^{+}$, respectively. In addition, the predictions about the masses and pole residues of the other $1D$ and $2D$ states of $Xi_{b}$ and $Lambda_{b}$ baryons in this paper are helpful in studying the D-wave bottom baryons in experiments in the future.



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