Identifying the $Λ_b(6146)^0$ and $Λ_b(6152)^0$ as $D$-wave bottom baryons

We study the $Λ_b(6146)^0$ and $Λ_b(6152)^0$ recently observed by LHCb using the method of QCD sum rules within the framework of heavy quark effective theory. Our results suggest that they can be interpreted as $D$-wave bottom baryons of $J^P = 3/2^+$ and $5/2^+$ respectively, both of which contain two $λ$-mode excitations. We also investigate other possible assignments containing $ρ$-mode excitations. We predict masses of their strangeness partners to be $m_{Ξ_b(3/2^+)} = 6.26^{+0.11}_{-0.14}$ GeV and $m_{Ξ_b(5/2^+)} = 6.26^{+0.11}_{-0.14}$ GeV with the mass splitting $ΔM = 4.5^{+1.9}_{-1.5}$ MeV, and propose to search for them in future LHCb and CMS experiments.

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